JavaScript获取字符串在另一个字符串内的最后一个字符的位置

Question

i guess the problem is extremely casual, but can't really find the solution.

i have a string

var full = 'hopaopGmailb3GkI'
var name = 'hopaop'
var service = 'Gmail'

How do i get the b3GkI from the original string , suppose the name and service are dynamic values also parsed from the string var full .

Or how to get the index of the last character of the variable service inside of the var full string

I need to get the index of the last character of the variable service inside of the var full string. var index = full.indexOf(service); returning the first character's index (6 in this example). Also for some reason i can't exclude name + service from the string.

Answer 1

var index = full.indexOf(service) + service.length; should do the trick. I also feel like you can come up with a regular expression to accomplish this, but I am no master.

Answer 2

Version 1

 var full = 'hopaopGmailb3GkI'; var name = 'hopaop'; var service = 'Gmail'; var result = full.substring(full.indexOf(service) + service.length) console.log(result); 

Version 2

you can use Split

 var full = 'hopaopGmailb3GkI'; var name = 'hopaop'; var service = 'Gmail'; var result = full.split(service)[1]; console.log(result); 

Answer 3

Another alternative with Regular Expressions

var full = 'hopaopGmailb3GkI';
var service = 'Gmail';

console.log((function(source, service) {
    var match = new RegExp('(.+)' + service + '(.+)').exec(source);
    return {
        'service': service,
        'name': match[1],
        'token': match[2]
    };
})(full, service));

Returns an object like {"service":"Gmail","name":"hopaop","token":"b3GkI"}