这是一个简答的表单验证,它包含有正则表达式,来限制用户的输入,如果不符合要求则会提示有误;这个代码也很简单。
<!DOCTYPE html> | |
<html> | |
<head lang="en"> | |
<meta charset="UTF-8"> | |
<title></title> | |
<style> | |
div{ | |
border: 2px solid; | |
width: 430px; | |
height: 220px; | |
} | |
h1{ | |
text-align: center; | |
} | |
.err{ | |
color: red; | |
} | |
.denglu{ | |
width: 290px; | |
height: 40px; | |
} | |
p{ | |
text-align: center; | |
} | |
</style> | |
</head> | |
<body> | |
<div> | |
<form action="#" method="post" id="myform" name="myform" onsubmit="return chkform()"> | |
<h1>登陆考试</h1> | |
<p> | |
<span style="letter-spacing: 0.3em;">用户名</span>: <input type="text" name="username"/> | |
<span class="err" id="errname"></span> | |
</p> | |
<p> | |
<span style="letter-spacing: 2em;">密</span>码: <input type="password" name="userpwd"/> | |
<span class="err" id="errpwd"></span> | |
</p> | |
<p> | |
<input type="submit" value="登陆" class="denglu"/> | |
</p> | |
</form> | |
</div> | |
<script> | |
var myform = document.myform; | |
myform.username.onblur=function(){ | |
var reg = /^[a-zA-Z]{4,100}$/; | |
var err = document.getElementById(‘errname‘); | |
if(reg.test(this.value)){ | |
err.innerHTML=‘√‘; | |
}else{ | |
err.innerHTML=‘ב; | |
} | |
}; | |
myform.userpwd.onblur=function(){ | |
var reg = /^\w{6,30}$/; | |
var err = document.getElementById(‘errpwd‘); | |
if(reg.test(this.value)){ | |
err.innerHTML=‘√‘; | |
}else{ | |
err.innerHTML=‘ב; | |
} | |
}; | |
function chkform(){ | |
myform.username.onblur(); | |
myform.userpwd.onblur(); | |
var spans = document.getElementsByTagName("span"); | |
for(var i=0; i<spans.length; i++){ | |
if(spans[i].className==‘err‘ && spans[i].innerHTML.length>0){ | |
return false; | |
} | |
} | |
return true; | |
} | |
</script> | |
</table> | |
</body> | |
</html> |
原文:http://www.cnblogs.com/host717/p/6624705.html