auto memory

输入框中
autocomplete="off"

<form method="POST" autocomplete="off">

实现一个文本框既能输入又能选

<script language="javascript">
 function add(val) {
        var all = document.getElementById("n");
        var max = all.options.length;
        for (var i=0;i<max;i++) {
            if (all.options[i].text==val) {
                 return;
            } 
        }
        all.options.add(new Option(val));
    }
</script>
<form name="form1">
<input type="text" size="20" name="m" value="hello"  onPaste="alert('请手工输入');return false" onBlur="add(this.value)" >
<select name="n" onChange="this.form.m.value=this.options[selectedIndex].text" id="n">
<option>hello</option>
<option>a</option>
</select>
</form>

下面是去掉空格

<script language="javascript">
 function add(val) {
        var all = document.getElementById("n");
        var max = all.options.length;
        if(val.replace(/(\s+)/,'')==''){
             return;
        }
        for (var i=0;i<max;i++) {
            if (all.options[i].text==val) {
                 return;
            } 
        }
        all.options.add(new Option(val));
    }
</script>
<form name="form1">
<input type="text" size="20" name="m" value="hello"  onPaste="alert('请手工输入');return false" onBlur="add(this.value)" >
<select name="n" onChange="this.form.m.value=this.options[selectedIndex].text" id="n">
<option>hello</option>
<option>a</option>
</select>
</form>