1

这是我的代码:

<input type="text" id="fname">
<input type="button" onclick = "b();" value="change" />

<script>
function b(){
    var fanme = document.getElementById('fname');
    if(fname.value){
        fname.value="";
    }else{
        fname.value="ffff";
    }
</script>

我试过这个,但是fname当我点击按钮两次时,'s 的值有时会改变。怎么了?在其他浏览器上没问题

4

2 回答 2

3

Try this : instead of Elements use Element and also close function with }.

function b(){
    var fanme = document.getElementById('fname');
    if(fname.value){
        fname.value="";
    }else{
        fname.value="ffff";
    }
}       
于 2013-04-08T06:22:02.980 回答
0

尝试这个,

<input type="text" id="fname">
<input type="button" onclick = "b();" value="change" />

<script>
function b(){
    var fanme = document.getElementById('fname').value;
    if(fname == "" || fname == null || fname == "null"){
         fanme  = "Set the value as you want";
    }else{
         //proceed 
    }
</script>
于 2013-04-08T06:29:00.087 回答