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Old Pedant · 10-09-2012, 12:58 AM

The problem is that Array.indexOf and String.indexOf are very very different.

String.indexOf indeed looks for a substring in the string.
But Array.indexOf looks for an array *ELEMENT* (the ENTIRE element) that matches the given test value.

So the quick answer to your question is: Write code!

Code:

function findSubstringInArray( ary, str )
{
    for ( var a = 0; a < ary.length; ++a )
    {
        if ( ary[a].indexOf(str) >= 0 ) { return a; } /* return element number of found match */
    }
    return -1; /* not found */
}

Now... If this is something you do all the time, you might want to extend the Array prototype to add a method that will do as you wish. But if it's something you only do in one place in one page, just use simple code as shown.

10-09-2012, 12:58 AM	PM User \| #2
Old Pedant Supreme Master coder! Join Date: Feb 2009 Posts: 23,200 Thanks: 59 Thanked 3,996 Times in 3,965 Posts	The problem is that Array.indexOf and String.indexOf are very very different. String.indexOf indeed looks for a substring in the string. But Array.indexOf looks for an array ELEMENT (the ENTIRE element) that matches the given test value. So the quick answer to your question is: Write code! Code: function findSubstringInArray( ary, str ) { for ( var a = 0; a < ary.length; ++a ) { if ( ary[a].indexOf(str) >= 0 ) { return a; } /* return element number of found match / } return -1; / not found */ } Now... If this is something you do all the time, you might want to extend the Array prototype to add a method that will do as you wish. But if it's something you only do in one place in one page, just use simple code as shown. __________________ An optimist sees the glass as half full. A pessimist sees the glass as half empty. A realist drinks it no matter how much there is.