Equivalent of PHP’s in_array() function
Posted on September 13, 2008, under JavaScript,
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Hello coders,
This is a JavaScript function that works like in_array() in PHP. Below is the function with a usage example:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE>Equivalent of PHP in_array() | JavaScript Library</TITLE>
<META NAME="Author" CONTENT="Bit Repository">
<META NAME="Keywords" CONTENT="in_array, php, javascript">
<META NAME="Description" CONTENT="Equivalent of PHP in_array() | JavaScript Library">
<SCRIPT LANGUAGE="JavaScript">
function in_array(string, array)
{
for (i = 0; i < array.length; i++)
{
if(array[i] == string)
{
return true;
}
}
return false;
}
var extensions = new Array("jpg","jpeg","gif","png","bmp");
/*
// Alternative way of creating the array
var extensions = new Array();
extensions[1] = "jpg";
extensions[0] = "jpeg";
extensions[2] = "gif";
extensions[3] = "png";
extensions[4] = "bmp";
*/
var str_to_check = "bmp";
if(in_array(str_to_check, extensions))
{
alert(str_to_check +" is in our array.");
}
else
{
alert(str_to_check +" is not in our array.");
}
</SCRIPT>
</HEAD>
<BODY>
</BODY>
</HTML>
If you have any comments or suggestions regarding this script please post them.
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- September 13, 2008
- article by Gabriel C.
- 6 comments
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6 Replies to "Equivalent of PHP’s in_array() function"
September 13, 2008 at 5:44 AM
More concise:
function in_array(string, array) {
for(var i=0; i<array.length; i++) {
if (array[i] == string) return true;
}
return false;
}
September 25, 2008 at 4:13 AM
Even better:
Array.prototype.in_array = function(str){
for(var i=0; i<this.length; i++)
if (this[i] == str)
return true;
return false
}
August 31, 2009 at 2:07 PM
Hey quick question. How the heck do you get javascript to work when there is a field name like: name=”state[]” due to php requirement for the check boxes??
January 18, 2010 at 7:59 PM
Even more concise (Array.prototype.in_array adds the fonction string in the array !) :
function in_array (string, array) {
for (i in array) if(array[i] == string) return true;
return false;
};
April 1, 2010 at 5:22 AM
Thank you for this code it helped out a lot.
In regards to John the POST variable automatically converts to a PHP array so that is how you do it. You loop through the PHP array equivalent.
May 25, 2010 at 8:41 PM
Hey, Nice post.
This one i found more detail…
http://mahtonu.wordpress.com/2010/04/01/inarray-in-javascript/