PanoramicData.NCalcExtensions 1.20.126

PanoramicData.NCalcExtensions

Introduction

This nuget package provides extension functions for NCalc.

The NCalc documentation can be found here (source code) and here (good explanation of built-in functions).

Functions

Function	Purpose	Notes
all()	Returns true if all values match the lambda expression, otherwise false.
any()	Returns true if any values match the lambda expression, otherwise false.
canEvaluate()	Determines whether ALL of the parameters can be evaluated. This can be used, for example, to test whether a parameter is set.
capitalize()	Capitalizes a string.
cast()	Cast an object to another (e.g. float to decimal).
changeTimeZone()	Change a DateTime's time zone.
concat()	Concatenates lists and objects.
contains()	Determines whether one string contains another.
convert()	Converts the output of parameter 1 into the result of parameter 2.
count()	Counts the number of items. Optionally, only count those that match a lambda.
dateTime()	Return the DateTime in the specified format as a string, with an optional offset.
dateTimeAsEpochMs()	Parses the input DateTime and outputs as milliseconds since the Epoch (1970-01-01T00:00Z).
dictionary()	Builds a Dictionary<string, object?> from the parameters provided.
distinct()	Returns only distinct items from the input.
endsWith()	Determines whether a string ends with another string.
extend()	Extends an existing object into a JObject with both the original and additional properties.
first()	Returns the first item in a list that matches a lambda or throws a FormatException if no items match.
firstOrDefault()	Returns the first item in a list that matches a lambda or null if no items match.
format()	Formats strings and numbers as output strings with the specified format.
getProperty()	Returns the value of a given property.
humanize()	Converts a value to a more readable format.
if()	Return one of two values, depending on the input function.
in()	Determines whether a value is in a set of other values.
indexOf()	Determines the first position of a string within another string.
isGuid()	Determines whether a value is a GUID, or is a string that can be converted to a GUID.
isInfinite()	Determines whether a value is infinite.
isNaN()	Determines whether a value is not a number.
isNull()	Determines whether a value is null.
isNullOrEmpty()	Determines whether a value is null or empty.
isNullOrWhiteSpace()	Determines whether a value is null, empty or white space.
isSet()	Determines whether a parameter is set.
itemAtIndex()	Determines the item at the given index.
jObject()	Creates a JObject from key/value pairs.
join()	Joins a list of strings into a single string.
jPath()	Selects a single value from a JObject using a JPath expression
lastIndexOf()	Determines the last position of a string within another string.
length()	Determines length of a string or IList.
list()	Emits a List<object?> and collapses down lists of lists to a single list.
listOf()	Emits a List<T>.
max()	Emits the maximum value, ignoring nulls.
min()	Emits the minimum value, ignoring nulls.
nullCoalesce()	Returns the first parameter that is not null, otherwise: null.
orderBy()	Orders an IEnumerable by one or more lambda expressions.
padLeft()	Pad the left of a string with a character to a desired string length.
parse()	Returns the conversion of a string to a new type.
parseInt()	Returns an integer version of a string.	Deprecated - use parse() or tryParse() instead)
regexGroup()	Selects a regex group capture.
regexIsMatch()	Determine whether a string matches a regex.
replace()	Replace a string with another string.
retrieve()	Retrieves a value from storage.
select()	Converts an IEnumerable using a lambda.
selectDistinct()	Converts an IEnumerable using a lambda and removes duplicates.
setProperties()	Sets properties on an existing object.
skip()	Skips a number of items in a list.
sort()	Sorts an IComparable ascending or descending.
split()	Splits a string on a given character into a list of strings.
startsWith()	Determines whether a string starts with another string.
store()	Stores a value for use later in the pipeline.
substring()	Retrieves part of a string.
sum()	Sums numeric items.
switch()	Return one of a number of values, depending on the input function.
take()	Takes a number of items from a list.
throw()	Throws an NCalcExtensionsException.
timeSpan()	Determines the amount of time between two DateTimes.
toDateTime()	Converts a string to a UTC DateTime. May take an optional inputTimeZone.
toLower()	Converts a string to lower case.
toString()	Converts any object to a string.
toUpper()	Converts a string to upper case.
try()	If a function throws an exception, return an alternate value.
tryParse()	Returns a boolean result of an attempted cast
typeOf()	Determines the C# type of the object.
where()	Filters an IEnumerable to bring back only those items that match a condition.

Usage

using PanoramicData.NCalcExtensions;

...
var calculation = "lastIndexOf('abcdefg', 'def')";
var nCalcExpression = new Expression(calculation);

// Add the extension functions
nCalcExpression.EvaluateFunction += NCalcExtensions.NCalcExtensions.Extend;

if (nCalcExpression.HasErrors())
{
	throw new FormatException($"Could not evaluate expression: '{calculation}' due to {nCalcExpression.Error}.");
}

return nCalcExpression.Evaluate();

Namespace safety

Note that we regularly extend this library to add new functions. For those that further extend the functions, it is important to avoid future potential namespace conflicts. For this reason, we guarantee that we will never use the underscore character in any future function name and we recommend that any functions that you add DO include an underscore. For example, if you had a project called "My Project", we suggest that you name your functions as follows:

• mp_myFunction1()
• mp_myFunction2()

Contributing

Pull requests are welcome! Please submit your requests for new functions in the form of pull requests.

Function documentation

all()

Purpose

Returns true if all values match the lambda expression, otherwise false.

Parameters

• list - the original list
• predicate - a string to represent the value to be evaluated
• nCalcString - the string to evaluate

Examples

• all(list(1, 2, 3, 4, 5), 'n', 'n < 3') : false
• all(list(1, 2, 3, 4, 5), 'n', 'n > 0 && n < 10') : true

---

any()

Purpose

Returns true if any values match the lambda expression, otherwise false.

Parameters

• list - the original list
• predicate - a string to represent the value to be evaluated
• nCalcString - the string to evaluate

Examples

• any(list(1, 2, 3, 4, 5), 'n', 'n < 3') : true
• any(list(1, 2, 3, 4, 5), 'n', 'n > 11') : false

---

canEvaluate()

Purpose

Determines whether ALL of the parameters can be evaluated. This can be used, for example, to test whether a parameter is set.

Parameters

• parameter1, parameter2, ...

Examples

• canEvaluate(nonExistent) : false
• canEvaluate(1) : true

---

capitalize()

Purpose

Capitalizes a string.

Parameters

• string

Examples

• capitalize('new year') : 'New Year'

---

cast()

Purpose

Cast an object to another (e.g. float to decimal).

Notes

The method requires that conversion of value to target type be supported.

Parameters

• inputObject
• typeString

Examples

• cast(0.3, 'System.Decimal')

---

changeTimeZone()

Purpose

Change a DateTime's time zone.

Notes

For a list of supported TimeZone names, see https://docs.microsoft.com/en-us/dotnet/api/system.timezoneinfo.findsystemtimezonebyid?view=netstandard-2.0

Parameters

• source DateTime
• source TimeZone name
• destination TimeZone name

Examples

• changeTimeZone(theDateTime, 'UTC', 'Eastern Standard Time')
• changeTimeZone(theDateTime, 'Eastern Standard Time', 'UTC')

---

concat()

Purpose

Concatenates lists and objects.

Notes

The examples all result in a List<object?> containing 4 integers: 1, 2, 3 and 4.

Parameters

• the lists or objects to concatenate

Examples

• concat(list(1, 2), list(3, 4))
• concat(list(1, 2, 3, 4))
• concat(1, 2, 3, 4)
• concat(list(1, 2, 3), 4)
• concat(1, list(2, 3, 4))

---

contains()

Purpose

Determines whether one string contains another.

Parameters

• string searched-in text
• string searched-for text

Examples

• contains('haystack containing needle', 'needle') : true
• contains('haystack containing only hay', 'needle') : false

---

convert()

Purpose

Converts the output of parameter 1 into the result of parameter 2.

Notes

Can be used to return an empty string instead of the result of parameter 1, which can be useful when the return value is not useful. The result of parameter 1 is available as the variable "value".

Parameters

• the value to calculate
• destination TimeZone name

Examples

• convert(anyFunction(), 'XYZ'): 'XYZ'
• convert(1 + 1, value + 1): 3

---

count()

Purpose

Counts the number of items. Optionally, only count those that match a lambda.

Parameters

• list - the original list
• predicate (optional) - a string to represent the value to be evaluated
• nCalcString (optional) - the string to evaluate

Examples

• count('a piece of string') : 17
• count(list(1, 2, 3, 4, 5)) : 5
• count(list(1, 2, 3, 4, 5), 'n', 'n > 3') : 2

---

dateTime()

Purpose

Return the DateTime in the specified format as a string, with an optional offset.

Parameters

• timeZone (only 'UTC' currently supported)
• format
• day offset
• hour offset
• minute offset
• second offset

Examples

• dateTime('UTC', 'yyyy-MM-dd HH:mm:ss', -90, 0, 0, 0) : 90 days ago (e.g. '2019-03-14 05:09')
• dateTime('UTC', 'yyyy-MM-dd HH:mm:ss') : now (e.g. '2019-03-14 05:09')

---

dateTimeAsEpochMs()

Purpose

Parses the input DateTime and outputs as milliseconds since the Epoch (1970-01-01T00:00Z).

Parameters

• input date string
• format

Examples

• dateTimeAsEpochMs('20190702T000000', 'yyyyMMddTHHmmssK') : 1562025600000

---

dictionary()

Purpose

Emits a Dictionary<string, object?>.

Parameters

• interlaced keys and values. You must provide an even number of parameters, and keys must evaluate to strings.

Examples

• dictionary('KEY1', 'Hello', 'KEY2', 'Goodbye') : a dictionary containing 2 values with keys KEY1 and KEY2, and string values
• dictionary('TRUE', true, 'FALSE', false) : a dictionary containing 2 values with keys TRUE and FALSE, and boolean values

---

distinct()

Purpose

Returns only distinct items from the input.

Parameters

• list - the original list

Examples

• distinct(list(1, 2, 3, 3, 3)) : list(1, 2, 3)

---

endsWith()

Purpose

Determines whether a string ends with another string.

Parameters

• longString
• shortString

Examples

• endsWith('abcdefg', 'fg') : true
• endsWith('abcdefg', 'fgh') : false

---

extend()

Purpose

Extends an existing object into a JObject with both the original and additional properties.

Parameters

• originalObject
• listOfAdditionalProperties

Examples

• extend(jObject('a', 1, 'b', null), list('c', 5)) : JObject with a=1, b=null and c=5

---

first()

Purpose

Returns the first item in a list that matches a lambda or throws a FormatException if no items match.

Parameters

• list
• predicate
• lambda expression as a string

Examples

• first(list(1, 5, 2, 3), 'n', 'n % 2 == 0') : 2
• first(list(1, 5, 7, 3), 'n', 'n % 2 == 0') : FormatException thrown

---

firstOrDefault()

Purpose

Returns the first item in a list that matches a lambda or null if no items match.

Parameters

• list
• predicate
• lambda expression as a string

Examples

• firstOrDefault(list(1, 5, 2, 3), 'n', 'n % 2 == 0') : 2
• firstOrDefault(list(1, 5, 7, 3), 'n', 'n % 2 == 0') : null

---

format()

Purpose

Formats strings and numbers as output strings with the specified format.

Parameters

• object (number or text)
• format: the format to use

• see C# number and date/time formatting
• weekOfMonth is the numeric week of month as would be shown on a calendar with one row per week with weeks starting on a Sunday
• weekOfMonthText is the same as weekOfMonth, but translated: 1: 'first', 2: 'second', 3: 'third', 4: 'forth', 5: 'last'
• weekDayOfMonth is the number of times this weekday has occurred within the month so far, including this one
• weekDayOfMonthText is the same as weekDayOfMonth, but translated: 1: 'first', 2: 'second', 3: 'third', 4: 'forth', 5: 'last'

• timeZone [optional] - see https://docs.microsoft.com/en-us/dotnet/api/system.timezoneinfo.findsystemtimezonebyid?view=netstandard-2.0

Examples

• format(1, '00') : '01'
• format(1.0, '00') : '01'
• format('2021-11-29', 'dayOfYear') : '333'
• format('2021-11-01', 'weekOfMonth') : 1
• format('2021-11-01', 'weekOfMonthText') : 'first'
• format('2021-11-28', 'weekOfMonth') : 5
• format('2021-11-28', 'weekOfMonthText') : 'last'
• format('2021-11-28', 'weekDayOfMonth') : 4
• format('2021-11-28', 'weekDayOfMonthText') : 'forth'
• format('01/01/2019', 'yyyy-MM-dd') : '2019-01-01'
• format(theDateTime, 'yyyy-MM-dd HH:mm', 'Eastern Standard Time') [where theDateTime is a .NET DateTime, set to DateTime.Parse("2020-03-13 16:00", CultureInfo.InvariantCulture)] : '2020-03-13 12:00'

---

getProperty()

Purpose

Gets an object's property.

Parameters

• sourceObject
• propertyName

Examples

• getProperty(toDateTime('2019-01-01', 'yyyy-MM-dd'), 'Year') : 2019 (int)

---

humanize()

Purpose

Humanizes the value text.

Parameters

• value
• timeUnit

Examples

• humanize(3600, 'seconds') : '1 hour'

---

if()

Purpose

Return one of two values, depending on the input function.

Parameters

• condition
• output if true
• output if false

Examples

• if(1 == 1, 'yes', 'no') : 'yes'
• if(1 == 2, 3, 4) : 4

---

in()

Purpose

Determines whether a value is in a set of other values.

Parameters

• list
• item

Examples

• in('needle', 'haystack', 'with', 'a', 'needle', 'in', 'it') : true
• in('needle', 'haystack', 'with', 'only', 'hay') : false

---

indexOf()

Purpose

Determines the first position of a string within another string.

Notes

The first character is position 0. Returns -1 if not present.

Parameters

• longString
• shortString

Examples

• indexOf('#abcabc#', 'abc') : 1
• indexOf('#abcabc#', 'abcd') : -1

---

isGuid()

Purpose

Determines whether a value is a GUID, or is a string that can be converted to a GUID.

Parameters

• value

Examples

• isGuid('9384EF0Z-38AD-4E8E-A24E-0ACD3273A401') : true
• isGuid('{9384EF0Z-38AD-4E8E-A24E-0ACD3273A401}') : true
• isGuid('abc') : false

---

isInfinite()

Purpose

Determines whether a value is infinite.

Parameters

• value

Examples

• isInfinite(1/0) : true
• isInfinite(0/1) : false

---

isNaN()

Purpose

Determines whether a value is not a number.

Parameters

• value

Examples

• isNaN(null) : true
• isNaN('abc') : true
• isNaN(1) : false

---

isNull()

Purpose

Determines whether a value is null.

Notes

Returns true if the value is:

• null; or
• it's a JObject and it's type is JTokenType.Null.

Parameters

• value

Examples

• isNull(1) : false
• isNull('text') : false
• isNull(bob) : true if bob is null
• isNull(null) : true

---

isNullOrEmpty()

Purpose

Determines whether a value is null or empty.

Notes

True if:

• null; or
• it's a JObject and it's type is JTokenType.Null or;
• it's a string and it's empty.

Parameters

• value

Examples

• isNullOrEmpty(null) : true
• isNullOrEmpty('') : true
• isNullOrEmpty(' ') : false
• isNullOrEmpty(bob) : true if bob is null or whitespace
• isNullOrEmpty(1) : false
• isNullOrEmpty('text') : false

---

isNullOrWhiteSpace()

Purpose

Determines whether a value is null, empty or whitespace.

Notes

Returns true is the value is:

• null; or
• it's a JObject and it's type is JTokenType.Null or;
• it's a string and it's empty or only contains whitespace characters (\r, \n, \t, or ' ').

Parameters

• value

Examples

• isNullOrWhiteSpace(null) : true
• isNullOrWhiteSpace('') : true
• isNullOrWhiteSpace(' ') : true
• isNullOrWhiteSpace(bob) : true if bob is null or whitespace
• isNullOrWhiteSpace(1) : false
• isNullOrWhiteSpace('text') : false

---

isSet()

Purpose

Determines whether a parameter is set.

Parameters

• parameter name

Examples

• isSet('a') : true/false depending on whether a is an available variable

---

itemAtIndex()

Purpose

Determines the item at the given index. The first index is 0.

Parameters

• parameter name

Examples

• itemAtIndex(split('a b c', ' '), 1) : 'b'

---

jObject()

Purpose

Creates a JObject from key/value pairs.

Parameters

• key1 (string)
• value1
• key2 (string)
• value2
• ...
• keyN
• valueN

Examples

• jObject('a', 1, 'b', null) : JObject{ "a": 1, "b": null}

---

join()

Purpose

Joins a list of strings into a single string.

Parameters

• parameter name

Examples

• join(split('a b c', ' '), ', ') : 'a, b, c'

---

jPath()

Purpose

Selects a single value from a JObject using a JPath expression

Parameters

• input JObject
• JPath string expression

Examples

sourceJObject JSON:

{
  "name": "bob",
  "numbers": [ 1, 2 ]
  "arrayList": [ 
	 { "key": "key1", "value": "value1" },
	 { "key": "key2", "value": "value2" } 
  ]
}

• jPath(sourceJObject, 'name') : 'bob'
• jPath(sourceJObject, 'size') : an exception is thrown
• jPath(sourceJObject, 'size', True) : null is returned
• jPath(sourceJObject, 'numbers[0]') : 1
• jPath(sourceJObject, 'arrayList[?(@key==\'key1\')]') : "value1"

---

lastIndexOf()

Purpose

Determines the last position of a string within another string. Returns -1 if not present.

Parameters

• longString
• shortString

Examples

• lastIndexOf('#abcabc#', 'abc') : 4
• lastIndexOf('#abcabc#', 'abcd') : -1

---

length()

Purpose

Determines length of a string or IList.

Parameters

• string or IList

Examples

• length('a piece of string') : 17
• length(split('a piece of string', ' ')) : 4

---

list()

Purpose

Emits a List<object?> and collapses down lists of lists to a single list.

Parameters

• the parameters

Examples

• list('', 1, '0')
• list(null, 1, '0')
• list(list(null, 1, '0'), 1, '0')

---

listOf()

Purpose

Emits a List<T>.

Parameters

• the type
• the parameters

Examples

• listOf('object?', '', 1, '0')
• listOf('object?', null, 1, '0')
• listOf('int?', 1, null, 3)
• listOf('string', '1', '2', 3) : throws an exception

---

max()

Purpose

Emits the maximum value, ignoring nulls.

Parameters

• the list
• optionally, a pair of parameters providing a lambda expression to be evaluated.

Examples

• max(listOf('int?', 1, null, 3)) : 3
• max(listOf('int', 1, 2, 3), 'x', 'x + 1') : 4
• max(listOf('string', '1', '2', '3')) : '3'
• max(listOf('string', '1', '2', '3'), 'x', 'x + x') : '33'

---

min()

Purpose

Emits the minimum value, ignoring nulls.

Parameters

• the list
• optionally, a pair of parameters providing a lambda expression to be evaluated.

Examples

• min(listOf('int?', 1, null, 3)) : 1
• min(listOf('int', 1, 2, 3), 'x', 'x + 1') : 2
• min(listOf('string', '1', '2', '3')) : '1'
• min(listOf('string', '1', '2', '3'), 'x', 'x + x') : '11'

---

nullCoalesce()

Purpose

Returns the first parameter that is not null, otherwise: null.

Parameters

• any number of objects

Examples

• nullCoalesce() : null
• nullCoalesce(1, null) : 1
• nullCoalesce(null, 1, 2, 3) : 1
• nullCoalesce(null, null, null) : null
• nullCoalesce(null, null, 'xxx', 3) : 'xxx'

---

orderBy()

Purpose

Orders an IEnumerable by one or more lambda expressions.

Parameters

• list - the original list
• predicate - a string to represent the value to be evaluated
• nCalcString1 - the first orderBy lambda expression
• nCalcString2 (optional) - the next orderBy lambda expression
• nCalcString... (optional) - the next orderBy lambda expression

Examples

• orderBy(list(34, 33, 2, 1), 'n', 'n') : list(1, 2, 33, 34)
• orderBy(list(34, 33, 2, 1), 'n', '-n') : list(34, 33, 2, 1)
• orderBy(list(34, 33, 2, 1), 'n % 32', 'n % 2') : list(34, 33, 1, 2)
• orderBy(list(34, 33, 2, 1), 'n % 2', 'n % 32') : list(33, 1, 34, 2)

---

padLeft()

Purpose

Pad the left of a string with a character to a desired string length.

Parameters

• stringToPad
• desiredStringLength (must be >=1)
• paddingCharacter

Examples

• padLeft('', 1, '0') : '0'
• padLeft('12', 5, '0') : '00012'
• padLeft('12345', 5, '0') : '12345'
• padLeft('12345', 3, '0') : '12345'

---

parse()

Purpose

Returns the conversion of a string to a numeric type. Supported types are:

• bool
• sbyte
• byte
• short
• ushort
• int
• uint
• long
• ulong
• double
• float
• decimal
• JArray (jArray also supported for backaward compatibility)
• JObject (jObject also supported for backaward compatibility)
• Guid

Parameters

• type (see above)
• text
• valueIfParseFails (optional)

Examples

• parse('int', '1') : 1
• parse('bool', 'x', null) : null
• parse('jObject', '{ "a" : 1 }', null) : null
• parse('jArray', '[ { "a" : 1 } ]', null) : null

---

parseInt()

Purpose

Returns an integer version of a string.

Parameters

• integerAsString

Examples

• parseInt('1') : 1

---

regexGroup()

Purpose

Selects a regex group capture

Parameters

• input
• regex
• zero-based capture index (default: 0)

Examples

• regexGroup('abcdef', '^ab(.+?)f$') : 'cde'
• regexGroup('abcdef', '^ab(.)+f$') : 'c'
• regexGroup('abcdef', '^ab(.)+f$', 1) : 'd'
• regexGroup('abcdef', '^ab(.)+f$', 2) : 'e'
• regexGroup('abcdef', '^ab(.)+f$', 10) : null

---

regexIsMatch()

Purpose

Determine whether a string matches a regex

Parameters

• input
• regex

Examples

• regexIsMatch('abcdef', '^ab.+') : true
• regexIsMatch('Zbcdef', '^ab.+') : false

---

replace()

Purpose

Replace a string with another string

Parameters

• haystackString
• needleString
• betterNeedleString

Examples

• replace('abcdefg', 'cde', 'CDE') : 'abCDEfg'
• replace('abcdefg', 'cde', '') : 'abfg'

---

retrieve()

Purpose

Retrieves a value from storage

Parameters

• key

Examples

• retrieve('thing')

---

select()

Purpose

Converts an IEnumerable using a lambda.

Parameters

• list - the original list
• predicate - a string to represent the value to be evaluated
• nCalcString - the value to evaluate to for each item in the list
• output list type - outputs a list of the specified type (optional)

Examples

• select(list(1, 2, 3, 4, 5), 'n', 'n + 1') : list(2, 3, 4, 5, 6)
• select(list(jObject('a', 1, 'b', '2'), jObject('a', 3, 'b', '4')), 'n', 'n', 'JObject') : list of JObjects

---

selectDistinct()

Purpose

Converts an IEnumerable using a lambda and removes duplicates.

Parameters

• list - the original list
• predicate - a string to represent the value to be evaluated
• nCalcString - the value to evaluate to for each item in the list

Examples

• selectDistinct(list(1, 2, 3, 3, 3), 'n', 'n + 1') : list(2, 3, 4)

---

setProperties()

Purpose

Sets properties on an existing object.

Parameters

• object - the original object
• property1 - the first new property name
• value1 - the first new property value
• propertyN (optional) - the nth new property name
• valueN (optional) - the nth new property value

Examples

• setProperties(jObject('a', 1, 'b', null), 'c', 'X') : jObject('a', 1, 'b', null, 'c', 'X')
• setProperties(jObject('a', 1, 'b', null), 'c', 'X', 'd', 'Y') : jObject('a', 1, 'b', null, 'c', 'X', 'd', 'Y')

---

skip()

Purpose

Skips a number of items in a list.

Notes

If the number of items to skip is greater than the number of items in the list, an empty list is returned.

Parameters

• the list to skip from
• the number of items to skip

Examples

• skip(list(1, 2, 3), 1): list(2, 3)

---

sort()

Purpose

Sorts an IComparable ascending or descending.

Parameters

• list - the original list
• direction (optional) - 'asc' is the default, 'desc' is the other option

Examples

• sort(list(2, 1, 3)) : list(1, 2, 3)
• sort(list(2, 1, 3), 'asc') : list(1, 2, 3)
• sort(list(2, 1, 3), 'desc') : list(3, 2, 1)
• sort(list('b', 'a', 'c'))) : list('a', 'b', 'c')

---

split()

Purpose

Splits a string on a given character into a list of strings.

Parameters

• longString
• character

Examples

• split('a bc d', ' ') : list('a', 'bc', 'd')

---

startsWith()

Purpose

Determines whether a string starts with another string.

Parameters

• longString
• shortString

Examples

• startsWith('abcdefg', 'ab') : true
• startsWith('abcdefg', 'cd') : false

---

store()

Purpose

Stores a value for use later in the pipeline

Returns

true

Parameters

• key
• value

Examples

• store('thing', 1) : true

---

substring()

Purpose

Retrieves part of a string. If more characters are requested than available at the end of the string, just the available characters are returned.

Parameters

• inputString
• startIndex
• length (optional)

Examples

• substring('haystack', 3) : 'stack'
• substring('haystack', 0, 3) : 'hay'
• substring('haystack', 3, 100) : 'stack'
• substring('haystack', 0, 100) : 'haystack'
• substring('haystack', 0, 0) : ''

---

sum()

Purpose

Sums numeric items. Optionally, perform a lambda on each one first.

Parameters

• list - the original list
• predicate (optional) - a string to represent the value to be evaluated
• nCalcString (optional) - the string to evaluate

Examples

• sum(list(1, 2, 3)) : 6
• sum(list(1, 2, 3), 'n', 'n * n') : 14

---

switch()

Purpose

Return one of a number of values, depending on the input function.

Parameters

• switched value
• a set of pairs: case_n, output_n
• if present, a final value can be used as a default. If the default WOULD have been returned, but no default is present, an exception is thrown.

Examples

• switch('yes', 'yes', 1, 'no', 2) : 1
• switch('blah', 'yes', 1, 'no', 2) : throws exception
• switch('blah', 'yes', 1, 'no', 2, 3) : 3

---

take()

Purpose

Takes a number of items from a list.

Notes

If a number is provided that is longer than the list, the full list is returned.

Parameters

• the list to take from
• the number of items to take

Examples

• take(list(1, 2, 3), 2): list(1, 2)
• take(list(1, 2, 3), 10): list(1, 2, 3)

---

throw()

Purpose

Throws an NCalcExtensionsException. Useful in an if().

Parameters

• message (optional)

Examples

• throw()
• throw('This is a message')
• if(problem, throw('There is a problem'), 5)

---

timeSpan()

Purpose

Determines the amount of time between two DateTimes. The following units are supported:

• Years
• Weeks
• Days
• Hours
• Minutes
• Seconds
• Milliseconds
• Any other string is handled with TimeSpan.ToString(timeUnit). See https://learn.microsoft.com/en-us/dotnet/standard/base-types/standard-timespan-format-strings

Parameters

• startDateTime
• endDateTime
• timeUnit

Examples

• timeSpan('2019-01-01 00:01:00', '2019-01-01 00:02:00', 'seconds') : 3600

---

toDateTime()

Purpose

Converts a string to a UTC DateTime. May take an optional inputTimeZone.

Notes

When using numbers as the first input parameter, provide it as a decimal (see examples, below) to avoid hitting an NCalc bug relating to longs being interpreted as floats.

Parameters

• inputString
• stringFormat
• inputTimeZone (optional) See https://docs.microsoft.com/en-us/dotnet/api/system.timezoneinfo.findsystemtimezonebyid?view=netstandard-2.0

Examples

• toDateTime('2019-01-01', 'yyyy-MM-dd') : A date time representing 2019-01-01
• toDateTime('2020-02-29 12:00', 'yyyy-MM-dd HH:mm', 'Eastern Standard Time') : A date time representing 2020-02-29 17:00:00 UTC
• toDateTime('2020-03-13 12:00', 'yyyy-MM-dd HH:mm', 'Eastern Standard Time') : A date time representing 2020-03-13 16:00:00 UTC
• toDateTime(161827200.0, 's', 'UTC') : A date time representing 1975-02-17 00:00:00 UTC
• toDateTime(156816000000.0, 'ms', 'UTC') : A date time representing 1974-12-21 00:00:00 UTC
• toDateTime(156816000000000.0, 'us', 'UTC') : A date time representing 1974-12-21 00:00:00 UTC

---

toLower()

Purpose

Converts a string to lower case.

Parameters

• string

Examples

• toLower('PaNToMIMe') : 'pantomime'

---

toString()

Purpose

Converts any object to a string

Parameters

• object
• format (optional)

Examples

• toString(1) : '1'
• toString(1000, 'N2') : '1,000.00'
• toString(DateTimeOffset, 'yyyy-MM-dd') : '2023-02-17'

---

toUpper()

Purpose

Converts a string to upper case.

Parameters

• string

Examples

• toUpper('PaNToMIMe') : 'PANTOMIME'

---

try()

Purpose

If a function throws an exception, return an alternate value.

Parameters

• function to attempt
• result to return if an exception is thrown (null is returned if this parameter is omitted and an exception is thrown)

Examples

• try(1, 'Failed') : 1
• try(throw('Woo')) : null
• try(throw('Woo'), 'Failed') : 'Failed'
• try(throw('Woo'), exception_message) : 'Woo'
• try(throw('Woo'), exception_type) : typeof(PanoramicData.NCalcExtensions.Exceptions.NCalcExtensionsException)
• try(throw('Woo'), exception_typeFullName) : 'PanoramicData.NCalcExtensions.Exceptions.NCalcExtensionsException'
• try(throw('Woo'), exception_typeName) : 'NCalcExtensionsException'
• try(throw('Woo'), exception) : The Exception object thrown by the throw function.

---

tryParse()

Purpose

Returns a boolean result of an attempted cast.

Parameters

• type
• value
• key - for use with the retrieve() function

Examples

• tryParse('int', '1', 'outputVariable') : true
• tryParse('int', 'string', 'outputVariable') : false

---

typeOf()

Purpose

Determines the C# type of the object.

Parameters

• parameter

Examples

• typeOf('text') : 'String'
• typeOf(1) : 'Int32'
• typeOf(1.1) : 'Double'
• typeOf(null) : null

---

where()

Purpose

Filters an IEnumerable to bring back only those items that match a condition.

Parameters

• list - the original list
• predicate - a string to represent the value to be evaluated
• nCalcString - the string to evaluate

Examples

• where(list(1, 2, 3, 4, 5), 'n', 'n < 3') : list(1, 2)
• where(list(1, 2, 3, 4, 5), 'n', 'n < 3 || n > 4') : list(1, 2, 5)