what is the best way to check if a string exists in another? [duplicate]

Question

Possible Duplicate:
JavaScript: string contains

I'm looking for an algorithm to check if a string exists in another.

For example:

'Hello, my name is jonh LOL.'.contains('Hello, my name is jonh'); //true 'LOL. Hello, my name is jonh'.contains('Hello, my name is jonh'); //true 

Thanks in advance.

Answer 1

Use indexOf:

'Hello, my name is jonh LOL.'.indexOf('Hello, my name is jonh') > -1; //true 'LOL. Hello, my name is jonh'.indexOf('Hello, my name is jonh') > -1; //true 

You can also extend String.prototype to have a contains function:

String.prototype.contains = function(substr) {   return this.indexOf(substr) > -1; } 'Hello, my name is jonh LOL.'.contains('Hello, my name is jonh'); //true 'LOL. Hello, my name is jonh'.contains('Hello, my name is jonh'); //true 

Answer 2

As Digital pointed out the indexOf method is the way to check. If you want a more declarative name like contains then you can add it to the String prototype.

String.prototype.contains = function(toCheck) {   return this.indexOf(toCheck) >= 0; } 

After that your original code sample will work as written