This function returns the position of the first occurrence of SUBSTR in STR, starting at the beginning (starting at zero), or from POSITION if specified.
Following is the simple syntax for this function −
index STR, SUBSTR, POSITION index STR, SUBSTR
This function returns -1 on failure otherwise Position of matching string (starting at zero for the first character).
Following is the example code showing its basic usage −
#!/usr/bin/perl $string = "That is test"; $index = index ($string, 'is'); print "Position of is in the string $index\n";
When above code is executed, it produces the following result −
Position of is in the string 5