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In javascript, is there an equivalent of String.indexOf(...) that takes a regular expression instead of a string for the first parameter, while still allowing a second parameter ? I need to do something like str.indexOf(/[abc]/ , i); and str.lastIndexOf(/[abc]/ , i); While String.search() takes a regexp as a parameter it does not allow me to specify a second argument! Edit: This turned out to be harder than I originally thought so I wrote a small test function to test all the provided solutions... it assumes regexIndexOf and regexLastIndexOf have been added to the String object. function test (str) { var i = str.length +2; while (i--) { if (str.indexOf('a',i) != str.regexIndexOf(/a/,i)) alert (['failed regexIndexOf ' , str,i , str.indexOf('a',i) , str.regexIndexOf(/a/,i)]) ; if (str.lastIndexOf('a',i) != str.regexLastIndexOf(/a/,i) ) alert (['failed regexLastIndexOf ' , str,i,str.lastIndexOf('a',i) , str.regexLastIndexOf(/a/,i)]) ; } } and I am testing as follow to make sure that at least for one character regexp, the result is the same as if we used indexOf //Look for the a among the xes test('xxx'); test('axx'); test('xax'); test('xxa'); test('axa'); test('xaa'); test('aax'); test('aaa');

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