我们做网站,经常需要打印页面指定区域的内容,而网上关于这块的说法很多,各种各样的打印控件也不少。但许多打印方案都不怎么好,至少我不喜欢,要么封装复杂,要么难以维护。
之前写了一个通用打印方法,是基于网上的一个最简洁的打印插件,然后添加了自己的一些内容操作,能满足很多打印需求。
但现在开发环境越来越复杂,要求越来越苛刻,导致有些效果打印不出来,只好继续想办法。终于在网上发现了一个基于canvas的打印插件,终于彻底解决了所有的打印问题。
现在总结下来,以供参考:
1.网上找的js打印插件
/* * Version 2.4.0 Copyright (C) 2013 * Tested in IE 11, FF 28.0 and Chrome 33.0.1750.154 * No official support for other browsers, but will TRY to accommodate challenges in other browsers. * Example: * Print Button: <div id="print_button">Print</div> * Print Area : <div class="PrintArea" id="MyId" class="MyClass"> ... html ... </div> * Javascript : <script> * $("div#print_button").click(function(){ * $("div.PrintArea").printArea( [OPTIONS] ); * }); * </script> * options are passed as json (example: {mode: "popup", popClose: false}) * * {OPTIONS} | [type] | (default), values | Explanation * --------- | --------- | ---------------------- | ----------- * @mode | [string] | (iframe),popup | printable window is either iframe or browser popup * @popHt | [number] | (500) | popup window height * @popWd | [number] | (400) | popup window width * @popX | [number] | (500) | popup window screen X position * @popY | [number] | (500) | popup window screen Y position * @popTitle | [string] | ('') | popup window title element * @popClose | [boolean] | (false),true | popup window close after printing * @extraCss | [string] | ('') | comma separated list of extra css to include * @retainAttr | [string[]] | ["id","class","style"] | string array of attributes to retain for the containment area. (ie: id, style, class) * @standard | [string] | strict, loose, (html5) | Only for popup. For html 4.01, strict or loose document standard, or html 5 standard * @extraHead | [string] | ('') | comma separated list of extra elements to be appended to the head tag */ (function($) { var counter = 0; var modes = { iframe : "iframe", popup : "popup" }; var standards = { strict : "strict", loose : "loose", html5 : "html5" }; var defaults = { mode : modes.iframe, standard : standards.html5, popHt : 500, popWd : 400, popX : 200, popY : 200, popTitle : '', popClose : false, extraCss : '', extraHead : '', retainAttr: ["id", "class", "style"] }; var settings = {};//global settings $.fn.printArea = function( options ) { $.extend( settings, defaults, options ); counter++; var idPrefix = "printArea_"; $( "[id^=" + idPrefix + "]" ).remove(); settings.id = idPrefix + counter; var $printSource = $(this); var PrintAreaWindow = PrintArea.getPrintWindow(); PrintArea.write( PrintAreaWindow.doc, $printSource ); setTimeout( function () { PrintArea.print( PrintAreaWindow ); }, 1000 ); }; var PrintArea = { print : function( PAWindow ) { var paWindow = PAWindow.win; $(PAWindow.doc).ready(function(){ paWindow.focus(); paWindow.print(); if ( settings.mode == modes.popup && settings.popClose ) setTimeout(function() { paWindow.close(); }, 2000); }); }, write : function ( PADocument, $ele ) { PADocument.open(); PADocument.write( PrintArea.docType() + "<html>" + PrintArea.getHead() + PrintArea.getBody( $ele ) + "</html>" ); PADocument.close(); }, docType : function() { if ( settings.mode == modes.iframe ) return ""; if ( settings.standard == standards.html5 ) return "<!DOCTYPE html>"; var transitional = settings.standard == standards.loose ? " Transitional" : ""; var dtd = settings.standard == standards.loose ? "loose" : "strict"; return '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01' + transitional + '//EN" "http://www.w3.org/TR/html4/' + dtd + '.dtd">'; }, getHead : function() { var extraHead = ""; var links = ""; var styles = ''; if ( settings.extraHead ) settings.extraHead.replace( /([^,]+)/g, function(m){ extraHead += m }); $(document).find("link") .filter(function () { // Requirement: <link> element MUST have rel="stylesheet" to be considered in print document var relAttr = $(this).attr("rel"); return ($.type(relAttr) === 'undefined') == false && relAttr.toLowerCase() == 'stylesheet'; }) .filter(function () { // Include if media is undefined, empty, print or all var mediaAttr = $(this).attr("media"); return $.type(mediaAttr) === 'undefined' || mediaAttr == "" || mediaAttr.toLowerCase() == 'print' || mediaAttr.toLowerCase() == 'all' }) .each(function () { links += '<link type="text/css" rel="stylesheet" media="print" href="' + $(this).attr("href") + '" />'; styles += '@import url("' + $(this).attr("href") + '") print;'; }); if ( settings.extraCss ) settings.extraCss.replace( /([^,\s]+)/g, function(m){ links += '<link type="text/css" rel="stylesheet" href="' + m + '">' }); return '<head><title>' + settings.popTitle + '</title>' + extraHead + links + '<style type="text/css"> @media print{a:link:after {content: ""}}</style></head>'; //return "<head><title>" + settings.popTitle + "</title>" + extraHead + links + "</head>"; }, getBody : function ( elements ) { var htm = ""; var attrs = settings.retainAttr; elements.each(function() { var ele = PrintArea.getFormData( $(this) ); var attributes = "" for ( var x = 0; x < attrs.length; x++ ) { var eleAttr = $(ele).attr( attrs[x] ); if ( eleAttr ) attributes += (attributes.length > 0 ? " ":"") + attrs[x] + "='" + eleAttr + "'"; } htm += '<div ' + attributes + '>' + $(ele).html() + '</div>'; }); return "<body>" + htm + "</body>"; }, getFormData : function ( ele ) { var copy = ele.clone(); var copiedInputs = $("input,select,textarea", copy); $("input,select,textarea", ele).each(function( i ){ var typeInput = $(this).attr("type"); if ($.type(typeInput) === 'undefined') typeInput = $(this).is("select") ? "select" : $(this).is("textarea") ? "textarea" : ""; var copiedInput = copiedInputs.eq( i ); if ( typeInput == "radio" || typeInput == "checkbox" ) copiedInput.attr( "checked", $(this).is(":checked") ); else if ( typeInput == "text" ) copiedInput.attr( "value", $(this).val() ); else if ( typeInput == "select" ) $(this).find( "option" ).each( function( i ) { if ( $(this).is(":selected") ) $("option", copiedInput).eq( i ).attr( "selected", true ); }); else if ( typeInput == "textarea" ) copiedInput.text( $(this).val() ); }); return copy; }, getPrintWindow : function () { switch ( settings.mode ) { case modes.iframe : var f = new PrintArea.Iframe(); return { win : f.contentWindow || f, doc : f.doc }; case modes.popup : var p = new PrintArea.Popup(); return { win : p, doc : p.doc }; } }, Iframe : function () { var frameId = settings.id; var iframeStyle = 'border:0;position:absolute;width:0px;height:0px;right:0px;top:0px;'; var iframe; try { iframe = document.createElement('iframe'); document.body.appendChild(iframe); $(iframe).attr({ style: iframeStyle, id: frameId, src: "#" + new Date().getTime() }); iframe.doc = null; iframe.doc = iframe.contentDocument ? iframe.contentDocument : ( iframe.contentWindow ? iframe.contentWindow.document : iframe.document); } catch( e ) { throw e + ". iframes may not be supported in this browser."; } if ( iframe.doc == null ) throw "Cannot find document."; return iframe; }, Popup : function () { var windowAttr = "location=yes,statusbar=no,directories=no,menubar=no,titlebar=no,toolbar=no,dependent=no"; windowAttr += ",width=" + settings.popWd + ",height=" + settings.popHt; windowAttr += ",resizable=yes,screenX=" + settings.popX + ",screenY=" + settings.popY + ",personalbar=no,scrollbars=yes"; var newWin = window.open( "", "_blank", windowAttr ); newWin.doc = newWin.document; return newWin; } }; })(jQuery);
2. 打开https://html2canvas.hertzen.com网站,下载或引用html2canvas.js。也可以去我的资源下载页面下载:点击打开链接
3. 打印代码样例:
<div id="printArea">test print content</div> <div id="printFrame"></div> <script type="text/javascript"> var printAreaDiv = document.getElementById('printArea'); //待打印区域dom对象 html2canvas(printAreaDiv) //代入打印对象参数,生成canvas图形 .then(function (canvas) {//返回canvas对象 var dataUrl = canvas.toDataURL();//获取canvas对象图形的外部url var newImg = document.createElement("img");//创建img对象 newImg.src = dataUrl;//将canvas图形url赋给img对象 $('#printFrame').append(newImg).printArea();//打印img,注意不能直接打印img对象,需要包裹一层div $('#printFrame').html(''); //打印完毕释放包裹层内容(图像) }); </script>是不是觉得超级简单 事实就是这么简单,因为别人都把工具做好了