关于对象自面量json

yyx520aiy520 2011-10-08 03:36:49

如何用它我的代码但是每次出错
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>MyHtml.html</title>

<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="this is my page">
<meta http-equiv="content-type" content="text/html; charset=GB18030">



<script type="text/javascript">

var temp ;

function recevie(val){
alert("hello");
temp = val;
}

var numberAdd={
firstNum:document.getElementById('firstNum').value,
secondNum:document.getElementById('secondNum').value,
result:document.getElementById('result')
//jia:parseInt(numberAdd.firstNum)+parseInt(numberAdd.secondNum),
//jian:parseInt(numberAdd.firstNum)-parseInt(numberAdd.secondNum),
//cheng:parseInt(numberAdd.firstNum)*parseInt(numberAdd.secondNum),
//chu:parseInt(numberAdd.firstNum)/parseInt(numberAdd.secondNum)
};

function jiSuan(){
alert(numberAdd.firstNum);
}

/*
function jiSuan(){
if(temp=="+"){

numberAdd.result.value =numberAdd.jia;
return;
}
if(temp=="-"){
numberAdd.result.value =numberAdd.jian;
//numberAdd.result.value = parseInt(numberAdd.firstNum)-parseInt(numberAdd.secondNum);
//return;
}
if(temp=="*"){
numberAdd.result.value =numberAdd.cheng;
//numberAdd.result.value = parseInt(numberAdd.firstNum)*parseInt(numberAdd.secondNum);
//return;
}
if(temp=="/"){
numberAdd.result.value =numberAdd.chu;
//numberAdd.result.value = parseInt(numberAdd.firstNum)/parseInt(numberAdd.secondNum);
//return;
}
}
*/
</script>

</head>

<body>

<input type="text" id="firstNum">
<select name="sel" id="sele" onChange="recevie(this.value);" >
<option>选择运算符</option>
<option value="+">+</option>
<option value="-" >-</option>
<option value="*" >*</option>
<option value="/">/</option>
</select>
<input type="text" id="secondNum"><input type="button" value="=" onclick="jiSuan();"><input type="text" readonly="readonly" id="result"><br/>

</body>
</html>

...全文

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手写 2011-10-08

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你可以尝试用命名空间来保持变量的安全性
用闭包的单例模式来进行方法封装

<html>

<head>

    <script type="text/javascript">

    var JsuanQi=new function(){

        var slef=this;

        this.getFirstNum=function(){return document.getElementById('firstNum').value;};

        this.getSecondNum=function(){return document.getElementById('secondNum').value;};

        this.getResult=function(){return document.getElementById('result').value;};

        this.jia=function(){return parseInt(slef.getFirstNum())+parseInt(slef.getSecondNum());};

        this.jian=function(){return parseInt(slef.getFirstNum())-parseInt(slef.getSecondNum());};

        this.cheng=function(){return parseInt(slef.getFirstNum())*parseInt(slef.getSecondNum());};

        this.chu=function(){return parseInt(slef.getFirstNum())/parseInt(slef.getSecondNum());};



        this.jiSuan=function(){

            var fu=document.getElementById('sele').value;

            var ret="";

            switch (fu){

                case "+":{ret=slef.jia();break;}

                case "-":{ret=slef.jian();break;}

                case "*":{ret=slef.cheng();break;}

                case "/":{ret=slef.chu();break;}

                default:{ret="";break;}

            }

           document.getElementById('result').value =ret;

        }

    }

    </script>

</head>

  <body>

  <input type="text" id="firstNum">

  <select name="sel" id="sele"  >

  <option>选择运算符</option>

  <option value="+">+</option>

  <option value="-" >-</option>

  <option value="*" >*</option>

  <option value="/">/</option>

  </select>

  <input type="text" id="secondNum">

  <input type="button" value="=" onclick="JsuanQi.jiSuan();">

  <input type="text" readonly="readonly" id="result"><br/>

  </body>

</html>

手写 2011-10-08

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脚本是预加载编译
var numberAdd={
firstNum:document.getElementById('firstNum').value,
secondNum:document.getElementById('secondNum').value,
result:document.getElementById('result')
//jia:parseInt(numberAdd.firstNum)+parseInt(numberAdd.secondNum),
//jian:parseInt(numberAdd.firstNum)-parseInt(numberAdd.secondNum),
//cheng:parseInt(numberAdd.firstNum)*parseInt(numberAdd.secondNum),
//chu:parseInt(numberAdd.firstNum)/parseInt(numberAdd.secondNum)
};
你这一段，如何能找到document.getElementById('firstNum').value？
当你声明变量var numberAdd={
firstNum:xxx的时候，他是找不到document.getElementById('firstNum')的，因为他还没有加载进来
建议将这些代码放到body的最下面或者进行window的load加载时运行