function verifynumeric(k){
        // onkeypress=verifynumeric(event)
                if (document.all){
                        switch (window.event.keyCode){
                        case  0:break; // arrow keys, function keys
                        case  8:break; // backspace
                        case 48:break;
                        case 49:break;
                        case 50:break;
                        case 51:break;
                        case 52:break;
                        case 53:break;
                        case 54:break;
                        case 55:break;
                        case 56:break;
                        case 57:break;
                        default:window.event.keyCode = 0;break;
                        }
                } else {
                        switch (k.which){
                        case  0:break; // arrow keys, function keys
                        case  8:break; // backspace
                        case 48:break;
                        case 49:break;
                        case 50:break;
                        case 51:break;
                        case 52:break;
                        case 53:break;
                        case 54:break;
                        case 55:break;
                        case 56:break;
                        case 57:break;
                        default:newKey(k);break;
                        }
                }
}
function verifyalphanumeric(k){
        // onkeypress=verifyalphanumeric(event)
        if (document.all){
                key = window.event.keyCode;
        } else {
                key = k.which;
        }

        switch (true){
        case (key==0)             :break;  // arrow keys, function keys
        case (key==8)             :break;  // backspace
        case (key==32)            :break;  // space
        case (key>=48 && key<=57) :break;  // 0-9
        case (key>=97 && key<=122):break;  // a-z
        case (key>=65 && key<=90) :break;  // A-Z
        case (key==39)            :break;  // apostrophe
        case (key==40 || key==41) :break;  // parens
        case (key==45)            :break;  // hyphen
        case (key==47)            :break;  // slash
        case (key==91 || key==93) :break;  // brackets
        default: ( document.all ? window.event.keyCode = 0 : newKey(k) );break;
        }
}
function verifyalpha(k){
        // onkeypress=verifyalpha(event)
        if (document.all){
                key = window.event.keyCode;
        } else {
                key = k.which;
        }

        switch (true){
        case (key==0)             :break;  // arrow keys, function keys
        case (key==8)             :break;  // backspace
        case (key>=97 && key<=122):break;  // a-z
        case (key>=65 && key<=90) :break;  // A-Z
        default: ( document.all ? window.event.keyCode = 0 : newKey(k) );break;
        }
}
function newKey(event) {
        // for Firefox
     var new_event=document.createEvent("KeyEvents");
     new_event.initKeyEvent("keypress", false, true, document.defaultView, false, false, false, false, 0, 0);
     event.preventDefault();
     event.target.dispatchEvent(new_event);
}
function screenwidth(){
        return screen.width;
}
function screenheight(){
        return screen.height;
}
function appname(){
        return navigator.appName
}
function referrer(){
        return escape(document.referrer);
}
// <script language="JavaScript" type="text/javascript" src="functions.js"></script>