<!doctype html>
<html>
<head>
<title>测试</title>
<script type="text/javascript">
function test(elements){
var elem = elements.form;
for(var i=0; i<elem.length; i++){
elem.onfocus = function(){
if(this.value.length > 1 || this.defaultValue == "请输入您的用户名"){
this.value = "";
}
}
elem.onblur = function(){
if(this.defaultValue = "" || this.value.length < 1){
this.value = this.defaultValue;
}
}
}
}
function demo(){
var doc = document.form;
for(var j=0; j<doc.length; j++){
test(doc[j]);
}
}
window.onload = demo;
</script>
</head>
<body>
<input type="text" value="请输入您的用户名" />
</body>
</html>
<html>
<head>
<title>测试</title>
<script type="text/javascript">
function test(elements){
var elem = elements.form;
for(var i=0; i<elem.length; i++){
elem.onfocus = function(){
if(this.value.length > 1 || this.defaultValue == "请输入您的用户名"){
this.value = "";
}
}
elem.onblur = function(){
if(this.defaultValue = "" || this.value.length < 1){
this.value = this.defaultValue;
}
}
}
}
function demo(){
var doc = document.form;
for(var j=0; j<doc.length; j++){
test(doc[j]);
}
}
window.onload = demo;
</script>
</head>
<body>
<input type="text" value="请输入您的用户名" />
</body>
</html>
估计错在这了。
<html>
<head>
<title>测试</title>
<script type="text/javascript">
function test1(fm){
var elem = fm.elements;
for(var i=0; i<elem.length; i++){
elem[i].onfocus = function(){
if(this.value.length > 1 || this.defaultValue == "请输入您的用户名"){
this.value = "";
}
}
elem[i].onblur = function(){
if(this.defaultValue == "" || this.value.length < 1){
this.value = this.defaultValue;
}
}
}
}
function demo(){
var doc = document.forms;
for(var j=0; j<doc.length; j++){
test1(doc[j]);
}
}
window.onload = demo;
</script>
</head>
<body>
<form name="fm">
<input type="text" value="请输入您的用户名" />
</form>
</body>
</html>
一点一点测,有助进步
j<doc.length这里有错
如果有name=”form“这样的元素是不会出现脚本错误的!