如何验证路径是否以字符串开头

I tried pretty much all the methods to test if path like this file:///c:/folder/texts/int.txt or file:///d:/folder/texts/int.txt starts with d:/ or a:/ or c:/ somothings with string :/ some one have an idea please I try to use for this

if(strpos($URL, "c:/")) $URL = $URL;
else $URL = "http://$URL";

but it test just if the url starts with c:/ and i would like that test if it beginning with somothing like "{a,b,c,.............,z}:/".

How about using preg_match with PHP?

if (preg_match("#[a-z]:/#", $URL))

This, however, assumes that the drive can be anywhere in the string, and therefore that the path in it is a valid one. If you want it to specifically start with file///drive:/, then use this instead:

if (preg_match("#^file///[a-z]:/#", $URL))

Use regex with this method you can check to see if a string matches a pattern, in the following code I check if the string = [a-z]:// (case insensitive). If it doesn't = that then I append c:// to the start of the string.

Change the url variable to what ever you want and run the code, it should pop-up with the url in the correct format.

DEMO

JQuery

var url = "working";
var re = /\w:////.*/
var x = url.search(re);

if(x != 0){
    url = "c://"+url;
}
alert(url);