正则相对简单些
function okHandle()
{
if(!/\S/.test(document.test.userName.value))
alert("用户名称不能为空!");
else if (!/\S/.test(document.test.passWord.value)document.test.userName.value)
alert("用户密码不能为空!");
else
alert("您填写正确!");
}
function okHandle()
{
if(!/\S/.test(document.test.userName.value))
alert("用户名称不能为空!");
else if (!/\S/.test(document.test.passWord.value)document.test.userName.value)
alert("用户密码不能为空!");
else
alert("您填写正确!");
}
test
function okHandle()
{
if(!/\S/.test(document.test.userName.value))
alert("用户名称不能为空!");
else if (!/\S/.test(document.test.passWord.value)document.test.userName.value)
alert("用户密码不能为空!");
else
alert("您填写正确!");
}
<head>
<title>J4_5 </title>
<script language="javascript">
function checkValid(s)
{
//你比较下代码就知道正则和一般的代码的代码量
if(s.replace(/^\s*|\s*$/,"")=="")return true;//去掉首尾空白
return false;
/*var len=s.length;
for(var i=0;i <len;i++)
{
if(s.charAt(i)!="")
{
return false;
}
}
return true; */
}
function okHandle()
{
if(checkValid(document.test.userName.value))
{
alert("用户名称不能为空!");
}
else if (checkValid(document.test.passWord.value))
{
alert("用户密码不能为空!");
}
else
{
alert("您填写正确!");
}
}
function cancelHandle()
{
document.test.userName.value="";
document.test.passWord.value="";
}
function errorHandler(errorMessage,URL,line)
{
var message="错误信息:"+errorMessage+"\n错误文档的URL:"+URL+"\n错误URL:"+line;
alert(message);
}
function erroreg()
{
alert(s);
}
onerror=errorHandler;
</script>
</head>
<body>
<form name="test">
<h3>示例:窗体交互事件 </h3>
<font size="2">用户名称: </font>
<input type="text" name="userName" />
<br /> <br />
<font size="2">用户密码: </font>
<input type="text" name="passWord" />
<br /> <br />
<input type="button" name="ok" value="确定" onClick="okHandle()"/>
<input type="button" name="cancle" value="取消" onClick="cancelHandle()" />
</form>
</body>
</html>
<head>
<title>J4_5 </title>
<script language="javascript">
function checkValid(s){
return (/^\s*$/.test(s));
}
function okHandle(){
if (checkValid(document.test.userName.value))
alert("用户名称不能为空!");
else if (checkValid(document.test.passWord.value))
alert("用户密码不能为空!");
else
alert("您填写正确!");
}
function errorHandler(errorMessage, URL, line){
var message = "错误信息:" + errorMessage + "\n错误文档的URL:" + URL + "\n错误URL:" + line;
alert(message);
}
function erroreg(){
alert(s);
}
onerror = errorHandler;
</script>
</head>
<body>
<form name="test">
<h3>示例:窗体交互事件 </h3>
<font size="2">用户名称: </font><input type="text" name="userName" />
<br/>
<br/>
<font size="2">用户密码: </font><input type="text" name="passWord" />
<br/>
<br/>
<input type="button" name="ok" value="确定" onClick="okHandle()"/> <input type="reset" value="取消"/>
</form>
</body>
</html>