前端将json数据转换为Excel文件下载

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前端将json数据转换为Excel文件下载

第一步安装需要的依赖：

npm i file-saver xlsx -S
npm i script-loader -D

第二步需要加载两个依赖包：

Blob.js 和 Export2Excel.js文件

可以百度下载这两个文件，也可以直接copy下面的代码。

Blob.js代码如下：

/* eslint-disable */
/* Blob.js
 * A Blob implementation.
 *
 * By Eli Grey, http://eligrey.com
 * By Devin Samarin, https://github.com/eboyjr
 * License: X11/MIT
 *   See LICENSE.md
 */
 
/*global self, unescape */
/*jslint bitwise: true, regexp: true, confusion: true, es5: true, vars: true, white: true,
 plusplus: true */
 
/*! @source http://purl.eligrey.com/github/Blob.js/blob/master/Blob.js */
(function (view) {
    "use strict";
    view.URL = view.URL || view.webkitURL;
    if (view.Blob && view.URL) {
        try {
            new Blob;
           return;
        } catch (e) {}
    }
 
    // Internally we use a BlobBuilder implementation to base Blob off of
 
    // in order to support older browsers that only have BlobBuilder
 
    var BlobBuilder = view.BlobBuilder || view.WebKitBlobBuilder || view.MozBlobBuilder || (function(view) {
            var get_class = function(object) {
                    return Object.prototype.toString.call(object).match(/^\[object\s(.*)\]$/)[1];}, FakeBlobBuilder = function BlobBuilder() {
                    this.data = [];},
                    FakeBlob = function Blob(data, type, encoding) {
                        this.data = data;
                        this.size = data.length;
                        this.type = type;
                        this.encoding = encoding;},
                    FBB_proto = FakeBlobBuilder.prototype,
                    FB_proto = FakeBlob.prototype,
                    FileReaderSync = view.FileReaderSync,
                    FileException = function(type) {
                        this.code = this[this.name = type];}, 
                    file_ex_codes = (
                    "NOT_FOUND_ERR SECURITY_ERR ABORT_ERR NOT_READABLE_ERR ENCODING_ERR "+ "NO_MODIFICATION_ALLOWED_ERR INVALID_STATE_ERR SYNTAX_ERR"             ).split(" "), 
                file_ex_code = file_ex_codes.length,
                real_URL = view.URL || view.webkitURL || view,
                real_create_object_URL = real_URL.createObjectURL,
                real_revoke_object_URL = real_URL.revokeObjectURL, 
                URL = real_URL, 
                btoa = view.btoa,
                atob = view.atob,
                ArrayBuffer = view.ArrayBuffer, 
                Uint8Array = view.Uint8Array;
 
            FakeBlob.fake = FB_proto.fake = true;
 
            while (file_ex_code--) {
                FileException.prototype[file_ex_codes[file_ex_code]] = file_ex_code + 1;}
            if (!real_URL.createObjectURL) {
               URL = view.URL = {};
            }
            URL.createObjectURL = function(blob) {
                var type = blob.type, data_URI_header;
                if (type === null) {
                    type = "application/octet-stream";
                }
                if (blob instanceof FakeBlob) {
                    data_URI_header = "data:" + type;
                    if (blob.encoding === "base64") {
                       return data_URI_header + ";base64," + blob.data;
                    } else if (blob.encoding === "URI") {
                        return data_URI_header + "," + decodeURIComponent(blob.data);
                    } if (btoa) {
                        return data_URI_header + ";base64," + btoa(blob.data);
                    } else {
                        return data_URI_header + "," + encodeURIComponent(blob.data);
                    }
                } else if (real_create_object_URL) {
                    return real_create_object_URL.call(real_URL, blob);
                }
            };
 
            URL.revokeObjectURL = function(object_URL) {
                if (object_URL.substring(0, 5) !== "data:" && real_revoke_object_URL) {
                    real_revoke_object_URL.call(real_URL, object_URL);
                }
 
            };
 
            FBB_proto.append = function(data/*, endings*/) {
                var bb = this.data;
                // decode data to a binary string
                if (Uint8Array && (data instanceof ArrayBuffer || data instanceof Uint8Array)) {
                    var str = "", buf = new Uint8Array(data), i = 0 , buf_len = buf.length;
                    for (; i < buf_len; i++) {
                        str += String.fromCharCode(buf[i]);
                    }
                    bb.push(str);
                } else if (get_class(data) === "Blob" || get_class(data) === "File") {
                    if (FileReaderSync) {
                        var fr = new FileReaderSync;
                        bb.push(fr.readAsBinaryString(data));
                    } else {
                        // async FileReader won't work as BlobBuilder is sync
                        throw new FileException("NOT_READABLE_ERR");
                    }
                } else if (data instanceof FakeBlob) {
                    if (data.encoding === "base64" && atob) {
                        bb.push(atob(data.data));
                    } else if (data.encoding === "URI") {
                        bb.push(decodeURIComponent(data.data));
                    } else if (data.encoding === "raw") {
                        bb.push(data.data);
                    }
                } else {
                    if (typeof data !== "string") {
                        data += ""; // convert unsupported types to strings
                    }
                    // decode UTF-16 to binary string
                    bb.push(unescape(encodeURIComponent(data)));
                }
            };
            FBB_proto.getBlob = function(type) {
                if (!arguments.length) {
                    type = null;
                }
                return new FakeBlob(this.data.join(""), type, "raw");
            };
 
            FBB_proto.toString = function() {
                return "[object BlobBuilder]";
            };
 
            FB_proto.slice = function(start, end, type) {
                var args = arguments.length;
                if (args < 3) {
                    type = null;
                }
                return new FakeBlob(
                    this.data.slice(start, args > 1 ? end : this.data.length), type, this.encoding
                );
            };
 
            FB_proto.toString = function() {
                return "[object Blob]";
            };
 
            FB_proto.close = function() {
                this.size = this.data.length = 0;
            };
 
            return FakeBlobBuilder;
 
        }(view));
 
    view.Blob = function Blob(blobParts, options) {
        var type = options ? (options.type || "") : "";
        var builder = new BlobBuilder();
        if (blobParts) {
            for (var i = 0, len = blobParts.length; i < len; i++) {
                builder.append(blobParts[i]);
            }
        }
        return builder.getBlob(type);
    };
 
}(typeof self !== "undefined" && self || typeof window !== "undefined" && window || this.content || this));

Export2Excel.js代码如下：

/* eslint-disable */
 
require('script-loader!file-saver');
 
require('script-loader!@/vendor/Blob');// 实际Blob引入地址
 
import XLSX from 'xlsx'
 
function generateArray(table) {
 
    var out = [];
 
    var rows = table.querySelectorAll('tr');
 
    var ranges = [];
 
    for (var R = 0; R < rows.length; ++R) {
 
        var outRow = [];
 
        var row = rows[R];
 
        var columns = row.querySelectorAll('td');
 
        for (var C = 0; C < columns.length; ++C) {
 
            var cell = columns[C];
 
            var colspan = cell.getAttribute('colspan');
 
            var rowspan = cell.getAttribute('rowspan');
 
            var cellValue = cell.innerText;
 
            if (cellValue !== "" && cellValue == +cellValue) cellValue = +cellValue;
 
            //Skip ranges
 
            ranges.forEach(function (range) {
 
                if (R >= range.s.r && R <= range.e.r && outRow.length >= range.s.c && outRow.length <= range.e.c) {
 
                    for (var i = 0; i <= range.e.c - range.s.c; ++i) outRow.push(null);
 
                }
 
            });
 
            //Handle Row Span
 
            if (rowspan || colspan) {
 
                rowspan = rowspan || 1;
 
                colspan = colspan || 1;
 
                ranges.push({s: {r: R, c: outRow.length}, e: {r: R + rowspan - 1, c: outRow.length + colspan - 1}});
 
            }
 
            ;
 
            //Handle Value
 
            outRow.push(cellValue !== "" ? cellValue : null);
 
            //Handle Colspan
 
            if (colspan) for (var k = 0; k < colspan - 1; ++k) outRow.push(null);
 
        }
 
        out.push(outRow);
 
    }
 
    return [out, ranges];
 
};
 
function datenum(v, date1904) {
 
    if (date1904) v += 1462;
 
    var epoch = Date.parse(v);
 
    return (epoch - new Date(Date.UTC(1899, 11, 30))) / (24 * 60 * 60 * 1000);
 
}
 
function sheet_from_array_of_arrays(data, opts) {
 
    var ws = {};
 
    var range = {s: {c: 10000000, r: 10000000}, e: {c: 0, r: 0}};
 
    for (var R = 0; R != data.length; ++R) {
 
        for (var C = 0; C != data[R].length; ++C) {
 
            if (range.s.r > R) range.s.r = R;
 
            if (range.s.c > C) range.s.c = C;
 
            if (range.e.r < R) range.e.r = R;
 
            if (range.e.c < C) range.e.c = C;
 
            var cell = {v: data[R][C]};
 
            if (cell.v == null) continue;
 
            var cell_ref = XLSX.utils.encode_cell({c: C, r: R});
 
            if (typeof cell.v === 'number') cell.t = 'n';
 
            else if (typeof cell.v === 'boolean') cell.t = 'b';
 
            else if (cell.v instanceof Date) {
 
                cell.t = 'n';
 
                cell.z = XLSX.SSF._table[14];
 
                cell.v = datenum(cell.v);
 
            }
 
            else cell.t = 's';
 
            ws[cell_ref] = cell;
 
        }
 
    }
 
    if (range.s.c < 10000000) ws['!ref'] = XLSX.utils.encode_range(range);
 
    return ws;
 
}
 
function Workbook() {
 
    if (!(this instanceof Workbook)) return new Workbook();
 
    this.SheetNames = [];
 
    this.Sheets = {};
 
}
 
function s2ab(s) {
 
    var buf = new ArrayBuffer(s.length);
 
    var view = new Uint8Array(buf);
 
    for (var i = 0; i != s.length; ++i) view[i] = s.charCodeAt(i) & 0xFF;
 
    return buf;
 
}
 
export function export_table_to_excel(id) {
 
    var theTable = document.getElementById(id);
 
    var oo = generateArray(theTable);
 
    var ranges = oo[1];
 
    /* original data */
 
    var data = oo[0];
 
    var ws_name = "SheetJS";
 
    var wb = new Workbook(), ws = sheet_from_array_of_arrays(data);
 
    /* add ranges to worksheet */
 
    // ws['!cols'] = ['apple', 'banan'];
 
    ws['!merges'] = ranges;
 
    /* add worksheet to workbook */
 
    wb.SheetNames.push(ws_name);
 
    wb.Sheets[ws_name] = ws;
 
    var wbout = XLSX.write(wb, {bookType: 'xlsx', bookSST: false, type: 'binary'});
 
    saveAs(new Blob([s2ab(wbout)], {type: "application/octet-stream"}), "test.xlsx")
 
}
 
export function export_json_to_excel(th, jsonData, defaultTitle) {
 
    /* original data */
 
    var data = jsonData;
 
    // console.log('th',th);
 
    // console.log('jsonData',jsonData);
 
    // console.log('defaultTitle',defaultTitle)
 
    data.unshift(th);
 
    var ws_name = "SheetJS";
 
    var wb = new Workbook(), ws = sheet_from_array_of_arrays(data);
 
    /*设置worksheet每列的最大宽度*/
 
    const colWidth = data.map(row => row.map(val => {
 
      /*先判断是否为null/undefined*/
 
      if (val == null) {
 
        return {'wch': 10};
 
      }
 
      /*再判断是否为中文*/
 
      else if (val.toString().charCodeAt(0) > 255) {
 
        return {'wch': val.toString().length * 2};
 
      } else {
 
        return {'wch': val.toString().length};
 
      }
 
    }))
 
    /*以第一行为初始值*/
 
    let result = colWidth[0];
 
    for (let i = 1; i < colWidth.length; i++) {
 
      for (let j = 0; j < colWidth[i].length; j++) {
 
        if (result[j]['wch'] < colWidth[i][j]['wch']) {
 
          result[j]['wch'] = colWidth[i][j]['wch'];
 
        }
 
      }
 
    }
 
    ws['!cols'] = result;
 
    /* add worksheet to workbook */
 
    wb.SheetNames.push(ws_name);
 
    wb.Sheets[ws_name] = ws;
 
    var wbout = XLSX.write(wb, {bookType: 'xlsx', bookSST: false, type: 'binary'});
 
    var title = defaultTitle || 'excel-list'
 
    saveAs(new Blob([s2ab(wbout)], {type: "application/octet-stream"}), title + ".xlsx")
 
}

第三步，在src目录下创建vendor文件夹，引入Blob.js和Export2Excel.js文件.

如果是按上面的方式创建并引入的，Export2Excel文件的引入目录就可以直接使用。

第四步，在vue中的使用方式:

如果你的数据就是完全下载的，不需要进行处理，则可以直接看代码，忽略下面的内容。

如果需要在数组中取出部分数据进行文件下载，可以查看该内容：blog.csdn.net/friend_ship…

下面是我的使用的代码

因为我的是获取单个对象数组来生成Excel表格，和原博主的用法不太一样

let rowXlsx = []
          rowXlsx.push(JSON.parse(row[j].data))//把对象加到数组里面去
          let keys = []
          let value = []
          rowXlsx.forEach((v,i)=>{        //获取key和value          
              Object.keys(v).forEach(v=>{
                keys.push(v)
                value.push(rowXlsx[i][v])
              })
          })
          console.log(keys)//取到了key
          console.log(value)//取到了值
          import("@/vendor/Export2Excel").then( excel => {//记得引入两个js文件
            const tHeader = keys;//这个是行头
            const filterVal = keys;//因为我的数组键值是用中文来做的，所以和行头是一样的，各人对应不一样的用法
            const content = rowXlsx;
            const data = this.formatJson(filterVal,content);
            excel.export_json_to_excel(tHeader,data,Date.parse(new Date()))
          })

formatJson(filterVal,jsonData) {
                return jsonData.map( v => filterVal.map(j=> v[j]))
            }

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