因为要修改默认placeholder的样式比较困难,用js模拟placeholder的效果
<!DOCTYPE HTML>
<html lang="zh-CN">
<head>
<meta charset="utf-8">
<title>模拟placeholder</title>
<meta name="viewport" content="width=device-width,initial-scale=1">
<link rel="stylesheet" href="http://cdn.static.runoob.com/libs/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="http://cdn.static.runoob.com/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://cdn.static.runoob.com/libs/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<style>
*{margin: 0;padding: 0}
div#main{
width:300px;
text-align: center;
}
.red{
color:red;
}
</style>
</head>
<body>
<input type="text" class="form-control red" value="请输入电话">
<script>
$(function(){
$('input').focus(function(){
if($(this).val()=='请输入电话'){
$(this).toggleClass('red');
$(this).val('');
}
});
$('input').blur(function(){
if($(this).val().trim()==''){
$(this).toggleClass('red');
$(this).val('请输入电话');
}
});
});
</script>
</body>
</html>