IE下支持文本框和密码框placeholder效果的JQuery插件
基于jQuery实现的,主要用于IE下实现placeholder效果,可同时支持文本和密码输入框。placeholder是HTML5新增的一个属性,当input设置了该属性后,该值的内容将作为灰色提示显示在文本框中,当文本框获得焦点时,提示文字消失。
实现代码如下:
(function($) {
/**
* 没有开花的树
* 2012/11/28 15:12
*/
var placeholderfriend = {
focus: function(s) {
s = $(s).hide().prev().show().focus();
var idValue = s.attr("id");
if (idValue) {
s.attr("id", idValue.replace("placeholderfriend", ""));
}
var clsValue = s.attr("class");
if (clsValue) {
s.attr("class", clsValue.replace("placeholderfriend", ""));
}
}
}
//判断是否支持placeholder
function isPlaceholer() {
var input = document.createElement('input');
return "placeholder" in input;
}
//不支持的代码
if (!isPlaceholer()) {
$(function() {
var form = $(this);
//遍历所有文本框,添加placeholder模拟事件
var elements = form.find("input[type='text'][placeholder]");
elements.each(function() {
var s = $(this);
var pValue = s.attr("placeholder");
var sValue = s.val();
if (pValue) {
if (sValue == '') {
s.val(pValue);
}
}
});
elements.focus(function() {
var s = $(this);
var pValue = s.attr("placeholder");
var sValue = s.val();
if (sValue && pValue) {
if (sValue == pValue) {
s.val('');
}
}
});
elements.blur(function() {
var s = $(this);
var pValue = s.attr("placeholder");
var sValue = s.val();
if (!sValue) {
s.val(pValue);
}
});
//遍历所有密码框,添加placeholder模拟事件
var elementsPass = form.find("input[type='password'][placeholder]");
elementsPass.each(function(i) {
var s = $(this);
var pValue = s.attr("placeholder");
var sValue = s.val();
if (pValue) {
if (sValue == '') {
//DOM不支持type的修改,需要复制密码框属性,生成新的DOM
var html = this.outerHTML || "";
html = html.replace(/\s*type=(['"])?password\1/gi, " type=text placeholderfriend")
.replace(/\s*(?:value|on[a-z]+|name)(=(['"])?\S*\1)?/gi, " ")
.replace(/\s*placeholderfriend/, " placeholderfriend value='" + pValue
+ "' " + "onfocus='placeholderfriendfocus(this);' ");
var idValue = s.attr("id");
if (idValue) {
s.attr("id", idValue + "placeholderfriend");
}
var clsValue = s.attr("class");
if (clsValue) {
s.attr("class", clsValue + "placeholderfriend");
}
s.hide();
s.after(html);
}
}
});
elementsPass.blur(function() {
var s = $(this);
var sValue = s.val();
if (sValue == '') {
var idValue = s.attr("id");
if (idValue) {
s.attr("id", idValue + "placeholderfriend");
}
var clsValue = s.attr("class");
if (clsValue) {
s.attr("class", clsValue + "placeholderfriend");
}
s.hide().next().show();
}
});
});
}
window.placeholderfriendfocus = placeholderfriend.focus;
})(jQuery);
使用很简单,html代码如下:
<html>
<head>
<script src="jquery.js" type="text/javascript"></script>
<script src="placeholderfriend.js" type="text/javascript"></script>
</head>
<body>
<input placeholder="账号/手机号码" ><br>
<input placeholder="密码" type="password" >
</body>
</html>