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I am trying to find some string part in another string. And I found a function called search() and tried this:

if("".search("http://") > 0){
  alert('with http');    
} else {
  alert('no http');   
}

but it is giving me no http even if it has http:// part in it. here is the fiddle: /

can you please help me out?

I am trying to find some string part in another string. And I found a function called search() and tried this:

if("http://www.google.de".search("http://") > 0){
  alert('with http');    
} else {
  alert('no http');   
}

but it is giving me no http even if it has http:// part in it. here is the fiddle: http://jsfiddle/xXTuY/2/

can you please help me out?

• javascript
• html
• split

Share Improve this question Follow edited Apr 28, 2013 at 6:09 intelis 8,0681414 gold badges6060 silver badges105105 bronze badges asked Apr 28, 2013 at 6:01 doniyordoniyor 38k6161 gold badges181181 silver badges270270 bronze badges 7

• 1 try reversing the condition – John Dvorak Commented Apr 28, 2013 at 6:03
• 1 search expects a regex, not a literal match – John Dvorak Commented Apr 28, 2013 at 6:05
• I've reverted ~ back to > -1 in my answer. Was that why you've unaccepted? – John Dvorak Commented Apr 28, 2013 at 6:20
• Please unaccept Chris' answer. He wants to delete it as it is incorrect. – John Dvorak Commented Apr 28, 2013 at 15:08
• @doniyor out of interest where are you getting the string http://www.google.de from? – Chris Moutray Commented Apr 28, 2013 at 15:38

 |  Show 2 more ments

2 Answers 2

Sorted by: Reset to default 9

First, String#search expects a regex, not a string. If it encounters a non-regex, it tries to convert it into a regex via new RegExp(patt). In case of a string, it treats the string as a regex pattern. This means that your search will behave unexpectedly (match more than desired, match less than desired or even throw a syntax error, if the string is not a valid regex) if the search string contains characters that have a special meaning in regular expressions. Use indexOf instead.

Second, search and indexOf return the position of the first match, or -1 if no match has been found. This means that if the return value is less than zero, nothing has been found. If the return value is zero, the match was made at the beginning of the string.

Also note there is a handy shortcut for x != -1: the bitwise negation ~x

if("http://www.google.de".indexOf("http://") > -1){
  alert('with http');    
} else {
  alert('no http');   
}

"http://www.google.de".search("http://") returns 0. 0 is not less than 0 so your condition evaluates to false.

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