在html5中,文本框,也就是input, type为text,或者password,新增了一个属性placeholder,也就是占位符,以下是firefox浏览器下的表现形式,当输入的时候,占位符就会消失。这个属性非常好用,因为有这个必要html5才会因素这个属性,然而在IE下,就没有这效果,以下是IE9的表现。
下面是JS版:
<!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title>跨浏览器placehoder</title> <meta name="author" content="ifrans.cn" /> <meta name="description" content="跨浏览器的placehoder原生js版,让ie也支持placehoder" /> <meta name="keywords" content="跨浏览器,placehoder,ie,原生js,表单" /> <style> body{font:12px/1.5 Arial,"\5b8b\4f53", sans-serif;-webkit-text-size-adjust:100%;color:#333333;background:white;} h1,h2,h3,h4,h5,h6,button,input,select,textarea{font-size:100%; font-weight:normal; font-style:normal;} table{border-collapse:collapse;border-spacing:0;font-size:100%;font:inherit;empty-cells:show} fieldset,img{border:0;} address,caption,cite,code,dfn,th,var{font-style:normal; font-weight:normal;} button,input,select,textarea{font-family:Arial, Helvetica, sans-serif;text-decoration: none;outline:none;-moz-outline:none;font-size:100%;} button,input{line-height:normal} button,select{text-transform:none} button,html input[type="button"],input[type="reset"],input[type="submit"]{vertical-align:middle;-webkit-appearance:button;cursor:pointer;} button[disabled],html input[disabled]{cursor:default} input[type="checkbox"],input[type="radio"]{box-sizing:border-box;padding:0;} input[type="search"]{-webkit-appearance:textfield;-moz-box-sizing:content-box;-webkit-box-sizing:content-box;box-sizing:content-box;} input[type="search"]::-webkit-search-cancel-button,input[type="search"]::-webkit-search-decoration{-webkit-appearance:none;} button::-moz-focus-inner,input::-moz-focus-inner{border:0;padding:0;} textarea{resize:none;overflow:auto;vertical-align:top} ul,ol,li,dl{list-style-type:none;} i,em{font-style:normal} svg:not(:root){overflow:hidden} img{vertical-align:middle;border:0;-ms-interpolation-mode:bicubic;-webkit-tap-highlight-color:rgba(0,0,0,0);} a{color:#333;text-decoration: none;outline:none;} a:link {color:#333;} a:visited {color:#333;} a:hover {color:#c00;text-decoration:underline;} a:active{blr:expression(this.onFocus=this.blur())} a:focus {outline:none;-moz-outline:none;} form{ width:300px; margin:20px auto 0;} h3{ font-weight:bold; margin:10px 0;} p{ margin-bottom:10px;} input{ vertical-align:middle; margin-left:10px; height:24px; line-height:24px; width:200px; padding-left:2px; border:1px #CCC solid;} textarea{ vertical-align:middle; margin-left:10px; width:200px; height:50px; font:inherit; padding-left:2px; border:1px #CCC solid;} .wrap-statistics{ visibility:hidden;} .dn{ display:none;} .db{ display:block;} .finps{ width:200px; height:24px;line-height:24px; border:1px #C30 solid; padding:0 5px; color:#000;} .oinps{width:200px; height:24px;line-height:24px; border:1px #CCC solid; padding:0 5px; color:#000;z-index:5;} .ftext{ width:200px; height:50px; border:1px #C30 solid; padding:0 5px; color:#000;} .otext{width:200px; height:50px; border:1px #CCC solid; padding:0 5px; color:#000;} </style> </head> <body> <form id="form1"> <h3>通过input方式模拟placeholder</h3> <p><label for="username1">用户名:</label><input type="text" name="username1" class="tst oinps" placeholder="请输入用户名" value="123" ></p> <p><label for="password1">密 码:</label><input type="password" name="password1" class="tst oinps" placeholder="请输入密码" value="" ></p> <p><label for="address1">地 址:</label><input type="text" name="address1" placeholder="请输入地址" value="" ></p> </form> <form id="form2"> <h3>通过textarea方式模拟placeholder</h3> <p><label for="remarks1">备 注:</label><textarea placeholder="请输入备注" class="otext" id="remarks1"></textarea></p> <p><label for="remarks2">备 注:</label><textarea placeholder="请输入备注" class="otext" id="remarks2"></textarea></p> <p><label for="remarks3">备 注:</label><textarea id="remarks3"></textarea></p> </form> <script> /** * @name placeHolder * @class 跨浏览器placeHolder,对于不支持原生placeHolder的浏览器,通过value或插入span元素两种方案模拟 * @param {Object} obj 要应用placeHolder的表单元素对象 */ function readyplace(element, type, handler){ if (element.addEventListener){ element.addEventListener(type, handler, false); } else if (element.attachEvent){ element.attachEvent("on" + type, handler); } else { element["on" + type] = handler; } } (function (window, undefined) { var hasClass = function(elem,sClass) { var sOldName=elem.className; if(sOldName) { sOldName=sOldName.split(‘ ‘); for(var i=0;i<sOldName.length;i++) { if(sOldName[i]==sClass) { return true; } } } } var addClass = function(elem,sClass) { if(!hasClass(elem,sClass)) { if(elem.className) { var sOldName=elem.className, blank = (sOldName != ‘‘) ? ‘ ‘ : ‘‘; elem.className=sOldName + blank + sClass; } else { elem.className=sClass; } } } var removeClass = function(elem,sClass) { var sOldName=elem.className.split(‘ ‘); var sNewClass=‘‘; for(var i=0;i<sOldName.length;i++) { if(sOldName[i] && sOldName[i]!=sClass) { sNewClass+=sOldName[i]+‘ ‘; } } elem.className=sNewClass.replace(/(^\s+)|(\s+$)/g, ‘‘); } var Place = (function() { return function(set){ this.tagName = set.tagName || "input" ; this.placeattr = set.placeattr || "placeholder" ; this.isempty = set.isempty ? true : false; this.focusCls = set.focusCls || "finps"; this.onblurCls = set.onblurCls || "oinps"; this.init(); } })(); Place.prototype = { init : function() { var elemTagName = document.getElementsByTagName(this.tagName); for(var i=0;i<elemTagName.length;i++){ this.create(elemTagName[i],this.isempty); } }, create:function(obj,isShow){ if (!obj.getAttribute(this.placeattr)) return; var getStyle = function(obj, prop) { if (obj.currentStyle) { //IE浏览器 return obj.currentStyle[prop]; } else if (window.getComputedStyle) { //W3C标准浏览器 return document.defaultView.getComputedStyle(obj, null)[prop]; } return null; }; var defaultValue = obj.getAttribute(this.placeattr); var placeHolderCont = document.createTextNode(defaultValue); var REPX=/px|em|rem/; var pat=parseInt(getStyle(obj,"paddingTop").replace(REPX,‘‘)) || 0; var par=parseInt(getStyle(obj,"paddingRight").replace(REPX,‘‘)) || 0; var pab=parseInt(getStyle(obj,"paddingBottom").replace(REPX,‘‘)) || 0; var pal=parseInt(getStyle(obj,"paddingLeft").replace(REPX,‘‘)) || 0; var mat=parseInt(getStyle(obj,"marginTop").replace(REPX,‘‘)) || 0; var mar=parseInt(getStyle(obj,"marginRight").replace(REPX,‘‘)) || 0; var mab=parseInt(getStyle(obj,"marginBottom").replace(REPX,‘‘)) || 0; var mal=parseInt(getStyle(obj,"marginLeft").replace(REPX,‘‘)) || 0; var fontSize = getStyle(obj, ‘fontSize‘); if (!obj.getAttribute("id")) { var idFor = "place" +Math.floor(Math.random().toString().substr(2,8)); }else{ var idFor =obj.getAttribute("id"); } obj.setAttribute("id", idFor); var LabelWrap = document.createElement(‘label‘); LabelWrap.setAttribute("for", idFor); LabelWrap.className = ‘placewrap‘; LabelWrap.style.cssText = ‘font-size:‘+fontSize+‘;position:absolute;cursor:text;text-indent:2px;z-index:5;top:‘+mat+‘px;left:‘+mal+‘px;padding:‘+pat+‘px ‘+par+‘px ‘+pab+‘px ‘+pal+‘px;color:#A9A9A9;‘; LabelWrap.style.width = obj.offsetWidth - (parseInt(getStyle(obj, ‘marginLeft‘), 10)||0) + ‘px‘; LabelWrap.style.lineHeight = obj.nodeName.toLowerCase() == ‘textarea‘ ? ‘‘: obj.offsetHeight-pat-pab + ‘px‘; var placebox=document.createElement("div"); placebox.className="labelwraps"; placebox.style.cssText=‘position:relative;visibility:visible;z-index:1;display:inline-block;‘; obj.parentNode.insertBefore(placebox,null); LabelWrap.appendChild(placeHolderCont); placebox.appendChild(LabelWrap); placebox.appendChild(obj); obj.removeAttribute(this.placeattr); LabelWrap.onclick = function() { obj.focus(); }; LabelWrap.style.display = obj.value == ‘‘ ? ‘block‘: ‘none‘; var changeHandler = function() { LabelWrap.style.display = obj.value != ‘‘ ? ‘none‘: ‘block‘; }; var that=this; if(!isShow){ obj.onclick = function() { if(obj.value == defaultValue && obj.value != ‘‘){ LabelWrap.style.display =‘block‘; removeClass(obj,that.onblurCls); addClass(obj,that.focusCls); }else { LabelWrap.style.display =‘none‘; removeClass(obj,that.onblurCls); addClass(obj,that.focusCls); } } obj.oninput = function() { if(obj.value != ‘‘){ LabelWrap.style.display =‘none‘; }else{ LabelWrap.style.display =‘block‘; } } obj.onblur = function() { if(obj.value != ‘‘){ LabelWrap.style.display =‘none‘; removeClass(obj,that.focusCls); addClass(obj,that.onblurCls); }else{ LabelWrap.style.display =‘block‘; removeClass(obj,that.focusCls); addClass(obj,that.onblurCls); } } //obj.onblur(); }else{ obj.onclick = function() { if(obj.value == defaultValue && obj.value != ‘‘){ removeClass(obj,that.onblurCls); addClass(obj,that.focusCls); }else { removeClass(obj,that.onblurCls); addClass(obj,that.focusCls); } }; obj.onblur = function() { if(obj.value != ‘‘){ removeClass(obj,that.focusCls); addClass(obj,that.onblurCls); }else{ removeClass(obj,that.focusCls); addClass(obj,that.onblurCls); } }; if (typeof(obj.oninput) == ‘object‘) { obj.addEventListener("input", changeHandler, false); } else { obj.onpropertychange = changeHandler; } }; return this; } } var placeholder = function(options) { new Place(options); } window.placeholder = placeholder; return placeholder; })(window); readyplace(document, ‘readystatechange‘, function(){ placeholder({focusCls:‘finps‘,onblurCls:‘oinps‘,isempty:false}); placeholder({tagName:‘textarea‘,focusCls:‘ftext‘,onblurCls:‘otext‘,isempty:true}); }) </script> </body> </html>
让IE支持placeholder属性,跨浏览器placehoder
时间: 2024-11-14 10:21:16