indexof()

Learn how to use the indexof() function to report the zero-based index position of the input string.

Reports the zero-based index of the first occurrence of a specified string within the input string.

For more information, see indexof_regex().

Syntax

indexof(string,match[,start[,length[,occurrence]]])

Parameters

NameTypeRequiredDescription
stringstring✔️The source string to search.
matchstring✔️The string for which to search.
startintThe search start position. A negative value will offset the starting search position from the end of the string by this many steps: abs(start).
lengthintThe number of character positions to examine. A value of -1 means unlimited length.
occurrenceintThe number of the occurrence. The default is 1.

Returns

The zero-based index position of match.

  • Returns -1 if match isn’t found in string.
  • Returns null if:
    • start is less than 0.
    • occurrence is less than 0.
    • length is less than -1.

Examples

print
 idx1 = indexof("abcdefg","cde")    // lookup found in input string
 , idx2 = indexof("abcdefg","cde",1,4) // lookup found in researched range 
 , idx3 = indexof("abcdefg","cde",1,2) // search starts from index 1, but stops after 2 chars, so full lookup can't be found
 , idx4 = indexof("abcdefg","cde",3,4) // search starts after occurrence of lookup
 , idx5 = indexof("abcdefg","cde",-5)  // negative start index
 , idx6 = indexof(1234567,5,1,4)       // two first parameters were forcibly casted to strings "12345" and "5"
 , idx7 = indexof("abcdefg","cde",2,-1)  // lookup found in input string
 , idx8 = indexof("abcdefgabcdefg", "cde", 1, 10, 2)   // lookup found in input range
 , idx9 = indexof("abcdefgabcdefg", "cde", 1, -1, 3)   // the third occurrence of lookup is not in researched range

Output

idx1idx2idx3idx4idx5idx6idx7idx8idx9
22-1-12429-1