jQuery: Check if character is in string

Question

I want the simplest way to check if an underscore (_) is in a variable using jQuery and do something if is not..

if ( '_ is not in var') {
 // Do
}

Thanks!

Answer 1

var str = "i am a string with _";
if (str.indexOf('_') == -1) {
 // will not be triggered because str has _..
}

and as spender said below on comment, jQuery is not a requirement.. indexOf is a native javascript

• spender: It's probably important to highlight to OP that the solution does not require jQuery, as demonstrated.
• Chris: Its worth noting that this isn't jQuery but basic javascript so could be used even without jQuery being loaded. The answer is correct of course, just a noteworthy addition given the question.

Answer 2

There are several ways to do this.

1. indexOf() method:

   if( str.indexOf('_') != -1 ){
    //do something
   }
   else{
    //do something 
   } 
   

2. Search() method:

    if( str.search("_")!=-1 ){
    //do something
    } 
    else {
    //Do something 
    }
   

3. :contains() selector:

    if( $("p:contains(_)") ).length{
    //Do something
    }
    else{
    //Do something
    }
   

4. using a regular expression:

    if( str.match(/_/g) ).length{
    //Do something
    }
    else{
    //Do something
    }
   

I think the first method is the simplest way.