Html转Word解决转存图片时候的跨域问题、视图问题

Html转Word解决转存图片时候的跨域问题、视图问题

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lmk1

演示视频

1.描述

想必很多人在开发项目的时候都遇到过这种需求,就是将一个html一键转成word,然后发现无论如何都没法将界面中的图片给保存下来,其实这是因为图片存在跨域的问题,目前我的解决办法是自己的图片保存在 七牛云 中,就不会出现这个问题了。如何你存储到其他的地方,比如自己的服务器,可能就需要开放自己的跨域(自行解决),如果你的图片是外部连接,比如csdn,这样是没法保存的,csdn上的图片不支持跨域请求。

2.Js代码

2.1.启动Js

function downloadword() {
    $("#paperque").wordExport(papername);  //fileName为导出的word文件的命名
    html2canvas(document.getElementById("paperque"), {
        onrendered: function (canvas) {
            //通过html2canvas将html渲染成canvas,然后获取图片数据
            var imgData = canvas.toDataURL('image/jpeg');
            //初始化pdf,设置相应格式
            var doc = new jsPDF("p", "mm", "a4");
            doc.setFillColor(0, 0, 0);
            //这里设置的是a4纸张尺寸
            doc.addImage(imgData, 'JPEG', 0, 0, 210, 297);
            //输出保存命名为content的pdf
            doc.save(papername + '.word');
        }
    });
}

2.2.wordexport.js

主要是下面这行代码

relimg.setAttribute("crossOrigin",'Anonymous');
if (typeof jQuery !== "undefined" && typeof saveAs !== "undefined") {
    (function($) {
        $.fn.wordExport = function(fileName) {
            fileName = typeof fileName !== 'undefined' ? fileName : "jQuery-Word-Export";
            var static = {
                mhtml: {
                    top: "Mime-Version: 1.0\nContent-Base: " + location.href + "\nContent-Type: Multipart/related; boundary=\"NEXT.ITEM-BOUNDARY\";type=\"text/html\"\n\n--NEXT.ITEM-BOUNDARY\nContent-Type: text/html; charset=\"utf-8\"\nContent-Location: " + location.href + "\n\n<!DOCTYPE html>\n<html>\n_html_</html>",
                    head: "<head>\n<meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\">\n<style>\n_styles_\n</style>\n</head>\n",
                    body: "<body>_body_</body>"
                }
            };
            var options = {
                maxWidth: 624
            };
            // Clone selected element before manipulating it
            var markup = $(this).clone();

            // Remove hidden elements from the output
            markup.each(function() {
                var self = $(this);
                if (self.is(':hidden'))
                    self.remove();
            });

            // Embed all images using Data URLs
            var images = Array();
            var img = markup.find('img');
            for (var i = 0; i < img.length; i++) {
                // Calculate dimensions of output image
                var w = Math.min(img[i].width, options.maxWidth);
                var h = img[i].height * (w / img[i].width);
                // Create canvas for converting image to data URL
                var canvas = document.createElement("CANVAS");
                canvas.width = w;
                canvas.height = h;
                // Draw image to canvas
                var context = canvas.getContext('2d'),
                    relimg = new Image(),//创建新的图片对象
                    base64 = '' ;//base64
                relimg.src = img[i].src;
                relimg.setAttribute("crossOrigin",'Anonymous'); //设置图片的跨域属性
                relimg.onload = function(){//图片加载完,再draw 和 toDataURL
                    context.drawImage(relimg,0, 0, w, h);
                    base64 = canvas.toDataURL("image/png");
                };
                // Get data URL encoding of image
                var uri = canvas.toDataURL("image/png");
                $(img[i]).attr("src", img[i].src);
                img[i].width = w;
                img[i].height = h;
                // Save encoded image to array
                images[i] = {
                    type: uri.substring(uri.indexOf(":") + 1, uri.indexOf(";")),
                    encoding: uri.substring(uri.indexOf(";") + 1, uri.indexOf(",")),
                    location: $(img[i]).attr("src"),
                    data: uri.substring(uri.indexOf(",") + 1)
                };
            }

            // Prepare bottom of mhtml file with image data
            var mhtmlBottom = "\n";
            for (var i = 0; i < images.length; i++) {
                mhtmlBottom += "--NEXT.ITEM-BOUNDARY\n";
                mhtmlBottom += "Content-Location: " + images[i].location + "\n";
                mhtmlBottom += "Content-Type: " + images[i].type + "\n";
                mhtmlBottom += "Content-Transfer-Encoding: " + images[i].encoding + "\n\n";
                mhtmlBottom += images[i].data + "\n\n";
            }
            mhtmlBottom += "--NEXT.ITEM-BOUNDARY--";

            //TODO: load css from included stylesheet
            var styles = "";

            // Aggregate parts of the file together
            var fileContent = static.mhtml.top.replace("_html_", static.mhtml.head.replace("_styles_", styles) + static.mhtml.body.replace("_body_", markup.html())) + mhtmlBottom;

            // Create a Blob with the file contents
            var blob = new Blob([fileContent], {
                type: "application/msword;charset=utf-8"
            });
            saveAs(blob, fileName + ".doc");
        };
    })(jQuery);
} else {
    if (typeof jQuery === "undefined") {
        console.error("jQuery Word Export: missing dependency (jQuery)");
    }
    if (typeof saveAs === "undefined") {
        console.error("jQuery Word Export: missing dependency (FileSaver.js)");
    }
}

2.2.fileSavers.js

/* FileSaver.js
 * A saveAs() FileSaver implementation.
 * 1.3.2
 * 2016-06-16 18:25:19
 *
 * By Eli Grey, http://eligrey.com
 * License: MIT
 *   See https://github.com/eligrey/FileSaver.js/blob/master/LICENSE.md
 */

/*global self */
/*jslint bitwise: true, indent: 4, laxbreak: true, laxcomma: true, smarttabs: true, plusplus: true */

/*! @source http://purl.eligrey.com/github/FileSaver.js/blob/master/FileSaver.js */

var saveAs = saveAs || (function(view) {
    "use strict";
    // IE <10 is explicitly unsupported
    if (typeof view === "undefined" || typeof navigator !== "undefined" && /MSIE [1-9]\./.test(navigator.userAgent)) {
        return;
    }
    var
        doc = view.document
        // only get URL when necessary in case Blob.js hasn't overridden it yet
        , get_URL = function() {
            return view.URL || view.webkitURL || view;
        }
        , save_link = doc.createElementNS("http://www.w3.org/1999/xhtml", "a")
        , can_use_save_link = "download" in save_link
        , click = function(node) {
            var event = new MouseEvent("click");
            node.dispatchEvent(event);
        }
        , is_safari = /constructor/i.test(view.HTMLElement)
        , is_chrome_ios =/CriOS\/[\d]+/.test(navigator.userAgent)
        , throw_outside = function(ex) {
            (view.setImmediate || view.setTimeout)(function() {
                throw ex;
            }, 0);
        }
        , force_saveable_type = "application/octet-stream"
        // the Blob API is fundamentally broken as there is no "downloadfinished" event to subscribe to
        , arbitrary_revoke_timeout = 1000 * 40 // in ms
        , revoke = function(file) {
            var revoker = function() {
                if (typeof file === "string") { // file is an object URL
                    get_URL().revokeObjectURL(file);
                } else { // file is a File
                    file.remove();
                }
            };
            setTimeout(revoker, arbitrary_revoke_timeout);
        }
        , dispatch = function(filesaver, event_types, event) {
            event_types = [].concat(event_types);
            var i = event_types.length;
            while (i--) {
                var listener = filesaver["on" + event_types[i]];
                if (typeof listener === "function") {
                    try {
                        listener.call(filesaver, event || filesaver);
                    } catch (ex) {
                        throw_outside(ex);
                    }
                }
            }
        }
        , auto_bom = function(blob) {
            // prepend BOM for UTF-8 XML and text/* types (including HTML)
            // note: your browser will automatically convert UTF-16 U+FEFF to EF BB BF
            if (/^\s*(?:text\/\S*|application\/xml|\S*\/\S*\+xml)\s*;.*charset\s*=\s*utf-8/i.test(blob.type)) {
                return new Blob([String.fromCharCode(0xFEFF), blob], {type: blob.type});
            }
            return blob;
        }
        , FileSaver = function(blob, name, no_auto_bom) {
            if (!no_auto_bom) {
                blob = auto_bom(blob);
            }
            // First try a.download, then web filesystem, then object URLs
            var
                filesaver = this
                , type = blob.type
                , force = type === force_saveable_type
                , object_url
                , dispatch_all = function() {
                    dispatch(filesaver, "writestart progress write writeend".split(" "));
                }
                // on any filesys errors revert to saving with object URLs
                , fs_error = function() {
                    if ((is_chrome_ios || (force && is_safari)) && view.FileReader) {
                        // Safari doesn't allow downloading of blob urls
                        var reader = new FileReader();
                        reader.onloadend = function() {
                            var url = is_chrome_ios ? reader.result : reader.result.replace(/^data:[^;]*;/, 'data:attachment/file;');
                            var popup = view.open(url, '_blank');
                            if(!popup) view.location.href = url;
                            url=undefined; // release reference before dispatching
                            filesaver.readyState = filesaver.DONE;
                            dispatch_all();
                        };
                        reader.readAsDataURL(blob);
                        filesaver.readyState = filesaver.INIT;
                        return;
                    }
                    // don't create more object URLs than needed
                    if (!object_url) {
                        object_url = get_URL().createObjectURL(blob);
                    }
                    if (force) {
                        view.location.href = object_url;
                    } else {
                        var opened = view.open(object_url, "_blank");
                        if (!opened) {
                            // Apple does not allow window.open, see https://developer.apple.com/library/safari/documentation/Tools/Conceptual/SafariExtensionGuide/WorkingwithWindowsandTabs/WorkingwithWindowsandTabs.html
                            view.location.href = object_url;
                        }
                    }
                    filesaver.readyState = filesaver.DONE;
                    dispatch_all();
                    revoke(object_url);
                }
            ;
            filesaver.readyState = filesaver.INIT;

            if (can_use_save_link) {
                object_url = get_URL().createObjectURL(blob);
                setTimeout(function() {
                    save_link.href = object_url;
                    save_link.download = name;
                    click(save_link);
                    dispatch_all();
                    revoke(object_url);
                    filesaver.readyState = filesaver.DONE;
                });
                return;
            }

            fs_error();
        }
        , FS_proto = FileSaver.prototype
        , saveAs = function(blob, name, no_auto_bom) {
            return new FileSaver(blob, name || blob.name || "download", no_auto_bom);
        }
    ;
    // IE 10+ (native saveAs)
    if (typeof navigator !== "undefined" && navigator.msSaveOrOpenBlob) {
        return function(blob, name, no_auto_bom) {
            name = name || blob.name || "download";

            if (!no_auto_bom) {
                blob = auto_bom(blob);
            }
            return navigator.msSaveOrOpenBlob(blob, name);
        };
    }

    FS_proto.abort = function(){};
    FS_proto.readyState = FS_proto.INIT = 0;
    FS_proto.WRITING = 1;
    FS_proto.DONE = 2;

    FS_proto.error =
        FS_proto.onwritestart =
            FS_proto.onprogress =
                FS_proto.onwrite =
                    FS_proto.onabort =
                        FS_proto.onerror =
                            FS_proto.onwriteend =
                                null;

    return saveAs;
}(
    typeof self !== "undefined" && self
    || typeof window !== "undefined" && window
    || this.content
));
// `self` is undefined in Firefox for Android content script context
// while `this` is nsIContentFrameMessageManager
// with an attribute `content` that corresponds to the window

if (typeof module !== "undefined" && module.exports) {
    module.exports.saveAs = saveAs;
} else if ((typeof define !== "undefined" && define !== null) && (define.amd !== null)) {
    define([], function() {
        return saveAs;
    });
}

3.使用

引入上面的js,网页中一个按钮,点击这个按钮调用downloadword函数即可,其中文件导出的文件名字可以自定义。

4.视图问题

上面运行后发现文档打开的页面不是 页面视图 ,而是 web视图 ,其实还需要修改wordexport.js。其中var static = {} 修改成如下内容。

var static = {
    mhtml: {
        top: "Mime-Version: 1.0\nContent-Base: " + location.href + "\nContent-Type: Multipart/related; boundary=\"NEXT.ITEM-BOUNDARY\";type=\"text/html\"\n\n--NEXT.ITEM-BOUNDARY\nContent-Type: text/html; charset=\"utf-8\"\nContent-Location: " + location.href + "\n\n<!DOCTYPE html>\n" +
        "<html xmlns:v=\"urn:schemas-microsoft-com:vml\" xmlns:o=\"urn:schemas-microsoft-com:office:office\" xmlns:w=\"urn:schemas-microsoft-com:office:word\" xmlns:m=\"http://schemas.microsoft.com/office/2004/12/omml\" xmlns=\"http://www.w3.org/TR/REC-html40\">\n_html_</html>",
        head: "<head>\n<meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\">\n<style>\n_styles_\n</style>\n<!--[if gte mso 9]><xml><w:WordDocument><w:View>Print</w:View><w:TrackMoves>false</w:TrackMoves><w:TrackFormatting/><w:ValidateAgainstSchemas/><w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid><w:IgnoreMixedContent>false</w:IgnoreMixedContent><w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText><w:DoNotPromoteQF/><w:LidThemeOther>EN-US</w:LidThemeOther><w:LidThemeAsian>ZH-CN</w:LidThemeAsian><w:LidThemeComplexScript>X-NONE</w:LidThemeComplexScript><w:Compatibility><w:BreakWrappedTables/><w:SnapToGridInCell/><w:WrapTextWithPunct/><w:UseAsianBreakRules/><w:DontGrowAutofit/><w:SplitPgBreakAndParaMark/><w:DontVertAlignCellWithSp/><w:DontBreakConstrainedForcedTables/><w:DontVertAlignInTxbx/><w:Word11KerningPairs/><w:CachedColBalance/><w:UseFELayout/></w:Compatibility><w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel><m:mathPr><m:mathFont m:val=\"Cambria Math\"/><m:brkBin m:val=\"before\"/><m:brkBinSub m:val=\"--\"/><m:smallFrac m:val=\"off\"/><m:dispDef/><m:lMargin m:val=\"0\"/> <m:rMargin m:val=\"0\"/><m:defJc m:val=\"centerGroup\"/><m:wrapIndent m:val=\"1440\"/><m:intLim m:val=\"subSup\"/><m:naryLim m:val=\"undOvr\"/></m:mathPr></w:WordDocument></xml><![endif]--></head>\n",
        body: "<body>_body_</body>"
    }
};

其实就是在html之间加入:

<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office"
xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml"
xmlns="http://www.w3.org/TR/REC-html40">

在head中加入:

<!--[if gte mso 9]><xml><w:WordDocument><w:View>Print</w:View><w:TrackMoves>false</w:TrackMoves><w:TrackFormatting/><w:ValidateAgainstSchemas/><w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid><w:IgnoreMixedContent>false</w:IgnoreMixedContent><w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText><w:DoNotPromoteQF/><w:LidThemeOther>EN-US</w:LidThemeOther><w:LidThemeAsian>ZH-CN</w:LidThemeAsian><w:LidThemeComplexScript>X-NONE</w:LidThemeComplexScript><w:Compatibility><w:BreakWrappedTables/><w:SnapToGridInCell/><w:WrapTextWithPunct/><w:UseAsianBreakRules/><w:DontGrowAutofit/><w:SplitPgBreakAndParaMark/><w:DontVertAlignCellWithSp/><w:DontBreakConstrainedForcedTables/><w:DontVertAlignInTxbx/><w:Word11KerningPairs/><w:CachedColBalance/><w:UseFELayout/></w:Compatibility><w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel><m:mathPr><m:mathFont m:val="Cambria Math"/><m:brkBin m:val="before"/><m:brkBinSub m:val="--"/><m:smallFrac m:val="off"/><m:dispDef/><m:lMargin m:val="0"/> <m:rMargin m:val="0"/><m:defJc m:val="centerGroup"/><m:wrapIndent m:val="1440"/><m:intLim m:val="subSup"/><m:naryLim m:val="undOvr"/></m:mathPr></w:WordDocument></xml><![endif]-->