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The SubString function extracts a string of specified length from a longer string in which it occurs.


string SubString(
  string searchString,
  int startingIndex,
  int length


  • searchString
    The string to be searched.

  • startingIndex
    The place in searchString where the string to be extracted begins.

  • Length
    The number of characters in the string to be extracted. Optional.

Return Values

Returns the specified string if present in searchString. If the specified string is not present, returns null.

The length argument is optional. If no value is passed, the function returns the string from startingIndex to the end of searchString.