JS development verification form tutorial - verification form (2)
As we mentioned in the previous section, verify whether the content of the form is empty. If it is empty, we will give a prompt message
Then let's look at how to remove the prompt message when entering content in the form text box or text field.
First of all, let’s think about the input content in the text box. This will trigger the keyboard event.
The code is as follows:
//When the text box of the user name triggers the keyboard event, prompt Information removal
Document.getElementById('name').onkeyup=function(){
Document.getElementById('sp').innerHTML = " ";
}
//When The password box trigger the keyboard event, prompt information to remove
DOCUMENT.GetelementByid ('PWD'). Onkeyup = Function () {
DOCUMENT.GetelementByid ('SP1'). }
// When the text box of the mailbox trigger the keyboard event, the prompt information removes
DOCumement.GelementByid ('SP2'). Ml = " ", sp3').innerHTML = " ";
}
The complete code is as follows:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<style type="text/css">
*{margin:0;padding:0;}
#div{width:410px;height:400px;background:#46a3ff;padding-left:16px;
padding-top:20px;}
input{
outline:none;
box-sizing:border-box;padding-left:15px;}
textarea{
outline:none;resize : none;
box-sizing:border-box;padding-left:15px;padding-top:5px;}
.name{width:200px;height:30px;margin-left:8px;border:1px solid #ffc1e0;border-radius:8px;}
.pwd{width:200px;height:30px;
margin-left:8px;border:1px solid #ffc1e0;border-radius:8px;}
.email{width:200px;height:30px;margin-left:8px;border:1px solid #ffc1e0;border-radius:8px;}
.txt{
width:280px;height:70px;margin-left:8px;border:1px solid #ffc1e0;border-radius:8px;}
.sub{width:100px;height:30px;padding-left:0px;
border:none;
border-radius:5px;background:#ffd0ff;}
.sub:hover{background:#ffaad5;}
.div{
width:200px;height:30px;margin:0 auto;box-sizing:border-box;padding-left:45px;padding-top:5px;color:#8600ff;font-weight:bold;}
</style>
</head>
<body>
<div id="div">
<form>
<label>用戶名:</label>
<input type="text" class="name" id="name">
<div id="sp" class="div"></div>
<label>密 碼:</label>
<input type="password" class="pwd" id="pwd">
<div id="sp1" class="div"></div>
<label>郵 箱:</label>
<input type="text" class="email" id="email">
<div id="sp2" class="div"></div>
<label>愛 好:</label>
<textarea rows="5" cols="40" class="txt" id="txt"></textarea>
<div id="sp3" class="div"></div>
<input type="button" class="sub" value="注冊" id="sub">
</form>
</div>
<script type="text/javascript">
var sub = document.getElementById('sub');
sub.onclick=function(){
//驗證用戶名是否為空,如果為空，給出提示信息
var val = document.getElementById('name').value;
if(val == ""){
document.getElementById("sp").innerHTML = "請輸入用戶名！";
}
//驗證密碼是否為空，為空則給出提示信息
var val1 = document.getElementById('pwd').value;
if(val1 == ""){
document.getElementById("sp1").innerHTML = "請輸入密碼！";
}
//驗證郵箱是否為空
var val2 = document.getElementById('email').value;
if(val2 == ""){
document.getElementById("sp2").innerHTML = "請輸入郵箱！";
}
//驗證內(nèi)容是否為空
var val3 = document.getElementById('txt').value;
if(val3 == ""){
document.getElementById("sp3").innerHTML = "請輸入內(nèi)容！";
}
}
//當(dāng)用戶名的文本框觸發(fā)鍵盤事件，提示信息去除
document.getElementById('name').onkeyup=function(){
document.getElementById('sp').innerHTML = " ";
}
//當(dāng)密碼框觸發(fā)鍵盤事件，提示信息去除
document.getElementById('pwd').onkeyup=function(){
document.getElementById('sp1').innerHTML = " ";
}
//當(dāng)郵箱文本框觸發(fā)鍵盤事件，提示信息去除
document.getElementById('email').onkeyup=function(){
document.getElementById('sp2').innerHTML = " ";
}
//當(dāng)文本域觸發(fā)鍵盤事件，提示信息去除
document.getElementById('txt').onkeyup=function(){
document.getElementById('sp3').innerHTML = " ";
}
</script>
</body>
</html>
