how to get a substring between two strings from a string in js code example

Example 1: javascript get text between two words

//Gets the part of the string inbetween the : and the ;
var part = str.substring(
    str.lastIndexOf(":") + 1, 
    str.lastIndexOf(";")
);

Example 2: how to get a substring between two strings from a string in js

//I would use indexOf instead of lastIndexOf, to find the first occurrence of the string