Javascript determines whether the file exists (client/server side)_javascript skills

Share how to use javascript to determine whether a file exists.

1. When judging client files, you can use

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. When judging the server side (network file), 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存在
else if(xmlhttp.status==404)s+=" doesn't exist."; //url不存在
else s+="";//其他状态
} // www.yuju100.com
alert(s);

You canSet contentEditable to false to restrict users to only select files, not just any Enter.