JavaScript determines whether a file exists (client/server side) _javascript Tips

Share the method of JavaScript to determine whether a file exists.

1, when you judge the client file, you can use the

var Fso,s=filespec; Filespec= "C:/path/myfile.txt"
fso=new activexobject ("Scripting.FileSystemObject");
if (FSO). FileExists (filespec))
s+= "exists.";
else//www.jb51.net
s+= "doesn ' t exist.";
alert (s);

2, to determine the server side (network files), you can use

var xmlhttp=new activexobject ("Microsoft.XMLHTTP");
Xmlhttp.open ("Get", yourfileurl,false);
Xmlhttp.send ();
if (xmlhttp.readystate==4) {
if (xmlhttp.status==200) s+= "exists."; URL exists
else if (xmlhttp.status==404) s+= "doesn ' t exist."; URL does not exist
else s+= "";//Other states
}//www.yuju100.com
alert (s);

You can <input style= "width:100%" type= "file" name= "id=" "contenteditable=" false > Set the contenteditable to False to restrict the user from selecting only files and not entering them casually.