Before (String function)

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Part of string before a substring (String class)

[Introduced in Model 204 7.5]

Before operates on a string and returns the portion of that string prior to the user-specified delimiter. To get the portion of the string after a delimiter, use the After string method.

Syntax

%outString = string:Before( substring, [Start= number])

Syntax terms

%outString A String or Longstring variable that must be long enough to hold the resulting parsed string. If a defined string length is shorter than needed to hold the result, a request canceling error occurs.
string A String or Longstring variable that holds the string to be parsed.
substring A String or Longstring variable that holds the separator character or characters on which parsing occurs.
Start A number that is the starting point for parsing. The default value is 1, indicating the beginning of the string. This is a name allowed argument, and it cannot be 0. If a value larger than the string is specified, the method returns a null string.

Usage notes

  • As the examples below show, if a starting value is entered, the %outString value is the content of the string beginning at the specified start point and ending at either of these:
    • The character before the first delimiter encountered after the start point.
    • The end of the string.
  • The delimiter string is not a list of individual delimiters, but a single delimiter which may be multiple characters. In other words, if your delimiter is ok, the method looks for occurrences of those two lowercase letters and returns a value from the string that precedes the occurrence of those letters.
  • Before is always case-sensitive.

Examples

The following request prints I am the Eggman:

begin %x is string len 64 initial('I am the Eggman! I am the Walrus! Koo Koo Kachoo!') printText {%x:before('!')} end

The following request prints Eggman:

begin %x is string len 64 initial('I am the Eggman! I am the Walrus! Koo Koo Kachoo!') printText {%x:before('!',start=10)} end

The following prints each blank-delimited word, one at a time:

begin %x is string len 64 initial('I am the Eggman! I am the Walrus! Koo Koo Kachoo!') repeat while %x:length print %x:before(' ') %x = %x:after(' ') end repeat end

See also