<html>
<head><script language="javascript">function chkvalue(txt)
{
if(txt.value=="")
{
alert("这里不能为空!");
document.form1.txt.onfocus();
}
else
{
if(!check(txt)) alert("请按正确的格式输入");
}
}
function check(str)
{
return str.match(\^[A-Za-z0-9_]{6,16}$\);
}
</script>
</head><body><form name="form1" action="" method="get" onsubmit="display()" target="_self">
姓 名:<input type="text" value="" name="name1" id="name1" onBlur="chkvalue(this)" /><br />
</form></body>
</html>
<head><script language="javascript">function chkvalue(txt)
{
if(txt.value=="")
{
alert("这里不能为空!");
document.form1.txt.onfocus();
}
else
{
if(!check(txt)) alert("请按正确的格式输入");
}
}
function check(str)
{
return str.match(\^[A-Za-z0-9_]{6,16}$\);
}
</script>
</head><body><form name="form1" action="" method="get" onsubmit="display()" target="_self">
姓 名:<input type="text" value="" name="name1" id="name1" onBlur="chkvalue(this)" /><br />
</form></body>
</html>
<head><script language="javascript">function chkvalue(txt)
{
if(txt.value=="")
{
alert("这里不能为空!");
txt.focus();
}
else
{
if(!check(txt.value)) alert("请按正确的格式输入");
}
}
function check(str)
{
return str.match(/^[A-Za-z0-9_]{6,16}$/);
}
</script>
</head><body><form name="form1" action="" method="get" onsubmit="display()" target="_self">
姓 名:<input type="text" value="" name="name1" id="name1" onBlur="chkvalue(this)" /><br />
</form></body>
</html>