表单文本输入框默认值的自动清除和恢复

HTML Code:

<div id="wp">
<input type="text" name="yourname" value="用户名" />
<input type="text" name="email" value="email" />
</div>

JS Code:
function init_input(id){
var inp = document.getElementById(id).getElementsByTagName('input');
for(var i = 0; i < inp.length; i++) {
if(inp[i].type == 'text') {
inp[i].setAttribute("rel",inp[i].defaultValue)
inp[i].onfocus = function() {
if(this.value == this.getAttribute("rel")) {
this.value = "";
} else {
this.select();
}
}
inp[i].onblur = function() {
if(this.value == "") {
this.value = this.getAttribute("rel");
}
}
}
}
}
init_input("wp");


转载来源：Jeff Starr的博客