表单的ajax验证,以post方式

表单验证很重要，极其重要。

首先，获取绑定对象的js函数是

function getActivatedObject(e) {

  var obj;

  if (!e) {

    // early version of IE

    obj = window.event.srcElement;

  } else if (e.srcElement) {

    // IE 7 or later

    obj = e.srcElement;

  } else {

    // DOM Level 2 browser

    obj = e.target;

  }

  return obj;

}

连接事件 和响应函数是

function addEventHandler(obj, eventName, handler) {

  if (document.attachEvent) {

    obj.attachEvent("on" + eventName, handler);

  } else if (document.addEventListener) {

    obj.addEventListener(eventName, handler, false);

  }

}

一般表单的验证函数为

非空的

function fieldIsFilled(e){

    var me=getActivatedObject(e);

    if(this.value==""){      

       \\ warn(me,"required");

    }else{

       \\ unwarn(me,"required"); 

    }

}

是字母的

function fieldIsLetters(e){

    var me=getActivatedObject(e);

    var nonAlphaChars=/[^a-zA-z]/;

    if(nonAlphaChars.test(me.value)){

        //desplay an error message

        warn(me,"letters");

    }else{

       unwarn(me,"letters"); 

    }

}

是数字的

function fieldIsNumbers(e){

    var me=getActivatedObject(e);

    var noNumbericChars=/[^0-9]/;

    if(noNumbericChars.test(me.value)){

        //desplay an error message

        warn(me,"letters");

    }else{

        unwarn(me,"letters");

    }

}

邮箱的格式验证：

function emailIsProper(e){

    var me = getActivatedObject(e);

    if(!/^[\w\.-_\+]+@[\w-]+(\.\w{2,4})+$/.test(me.value)){

        warn(me,"letters");

    }else{

       unwarn(me,"letters"); 

    }

}

验证举例：

addEventHandler(document.getElementById("email"),"blur",fieldIsFilled);

post方式提交ajax的区别

    var url = "register.php";

    var requestData="username=" +

      escape(document.getElementById("username").value) + "&password=" +

      escape(document.getElementById("password1").value) + "&firstname=" +

      escape(document.getElementById("firstname").value) + "&lastname=" +

      escape(document.getElementById("lastname").value) + "&email=" +

      escape(document.getElementById("email").value) + "&genre=" +

      escape(document.getElementById("genre").value) + "&favorite=" +

      escape(document.getElementById("favorite").value) + "&tastes=" +

      escape(document.getElementById("tastes").value);

    registerRequest.onreadystatechange = registrationProcessed;

    registerRequest.open("POST", url, true);

    registerRequest.setRequestHeader("Content-Type","application/x-www-form-urlencoded");

    registerRequest.send(requestData);

不需要回调，url不在附加信息，信息自己打包成requestData，要设置发送的文件头，方便服务器解析

 registerRequest.setRequestHeader("Content-Type","application/x-www-form-urlencoded");