自己编写了一个表单验证插件，使用起来很简单，以后还可以扩展更多的功能，比如ajax验证。
每个需要验证的表单元素下面有一个span标签，这个标签的class有一个valid表示需要验证，如果有nullable则表示可为空；rule表示验证规则，msg表示错误提示信息；to表示要验证的元素的name值，如果元素是单个的，to可以不写。该插件会遍历每个有valid的span标签，找出它前面需要验证的元素，根据rule验证，如果验证不通过，则显示边框为红色，鼠标放在元素上时显示错误信息。
验证时机：1、点击提交按钮时显式调用验证方法；2、当元素触发blur时验证。
插件代码：
CSS：
.failvalid{ border: solid 2px red !important;} JS：
/*** 2014年12月22日* 验证插件*/SimpoValidate = { //验证规则 rules: { int: /^[1-9]\d*$/, number: /^[+-]?\d*\.?\d+$/ }, //初始化 init: function () { $("span[class*='valid']").each(function () { //遍历span var validSpan = $(this); var to = validSpan.attr("to"); var target; if (to) { target = $("input[name='" + to + "'],select[name='" + to + "'],textarea[name='" + to + "']"); } else { var target = validSpan.prev(); } if (target) { target.blur(function () { SimpoValidate.validOne(target, validSpan); }); } }); }, //验证全部，验证成功返回true valid: function () { var bl = true; $("span[class*='valid']").each(function () { //遍历span var validSpan = $(this); var to = validSpan.attr("to"); var target; if (to) { target = $("input[name='" + to + "'],select[name='" + to + "'],textarea[name='" + to + "']"); } else { target = validSpan.prev(); } if (target) { if (!SimpoValidate.validOne(target, validSpan)) { bl = false; } } }); return bl; }, //单个验证，验证成功返回true validOne: function (target, validSpan) { SimpoValidate.removehilight(target, msg); var rule = SimpoValidate.getRule(validSpan); var msg = validSpan.attr("msg"); var nullable = validSpan.attr("class").indexOf("nullable") == -1 ? false : true; //是否可为空 var to = validSpan.attr("to"); if (target) { //checkbox或radio if (target[0].tagName.toLowerCase() == "input" && target.attr("type") && (target.attr("type").toLowerCase() == "checkbox" || target.attr("type").toLowerCase() == "radio")) { var checkedInput = $("input[name='" + to + "']:checked"); if (!nullable) { if (checkedInput.length == 0) { SimpoValidate.hilight(target, msg); return false; } } } //input或select if (target[0].tagName.toLowerCase() == "input" || target[0].tagName.toLowerCase() == "select") { var val = target.val(); if (!nullable) { if ($.trim(val) == "") { SimpoValidate.hilight(target, msg); return false; } } else { if ($.trim(val) == "") { SimpoValidate.removehilight(target, msg); return true; } } if (rule) { var reg = new RegExp(rule); if (!reg.test(val)) { SimpoValidate.hilight(target, msg); return false; } } } else if (target[0].tagName.toLowerCase() == "textarea") { var val = target.text(); if (!nullable) { if ($.trim(val) == "") { SimpoValidate.hilight(target, msg); return false; } } else { if ($.trim(val) == "") { SimpoValidate.removehilight(target, msg); return true; } } if (rule) { var reg = new RegExp(rule); if (!reg.test(val)) { SimpoValidate.hilight(target, msg); return false; } } } } return true; }, //获取验证规则 getRule: function (validSpan) { var rule = validSpan.attr("rule"); switch ($.trim(rule)) { case "int": return this.rules.int; case "number": return this.rules.number; default: return rule; break; } }, //红边框及错误提示 hilight: function (target, msg) { target.addClass("failvalid"); target.bind("mouseover", function (e) { SimpoValidate.tips(target, msg, e); }); target.bind("mouseout", function () { SimpoValidate.removetips(); }); }, //取消红边框及错误提示 removehilight: function (target) { target.unbind("mouseover"); target.unbind("mouseout"); target.removeClass("failvalid"); SimpoValidate.removetips(); }, //显示提示 tips: function (target, text, e) { var divtipsstyle = "position: absolute; left: 0; top: 0; background-color: #dceaf2; padding: 3px; border: solid 1px #6dbde4; visibility: hidden; line-height:20px; "; $("body").append(" " + text + " "); var divtips = $(".div-tips"); divtips.css("visibility", "visible"); var top = e.clientY + $(window).scrollTop() - divtips.height() - 18; var left = e.clientX; divtips.css("top", top); divtips.css("left", left); $(target).mousemove(function (e) { var top = e.clientY + $(window).scrollTop() - divtips.height() - 18; var left = e.clientX; divtips.css("top", top); divtips.css("left", left); }); }, //移除提示 removetips: function () { $(".div-tips").remove(); }};$(function () { SimpoValidate.init();}); 如何使用：
1、引用CSS和JS(必须引用jQuery)：
2、表单HTML代码(部分代码)：
| 多 少 |
| 狗 猫 |
3、执行验证JS代码：
//保存数据function save() { if (SimpoValidate.valid()) { //执行验证 $("#frm").submit(); //提交表单 }} 效果图：
