nodejs實現點擊下載EXCEL

首先在libs下建立一個文件

裏面的內容爲

const fs = require('fs');
class Download {

    constructor(ctx) {
        this.ctx = ctx;
        this.cols = [];
        this.rows = [];
    }

    newRow() {
        if (this.cols.length > 0) {
            this.rows.push(this.cols.join(","));
        }
        this.cols = [];
        return this;
    }

    addCol(val) {
        this.cols.push(val);
        return this;
    }

    output(filename) {
        let content = this.rows.join("\r\n");
        let data = Buffer.concat([Buffer.from('\xEF\xBB\xBF', 'binary'), Buffer.from(content)]);
        this.ctx.set('Content-Type', 'application/vnd.openxmlformats; charset=utf-8');
        this.ctx.set("Content-Disposition", "attachment; filename=" + filename);
        return data;
    }

    save(filename) {
        let content = this.rows.join("\r\n");
        let data = Buffer.concat([Buffer.from('\xEF\xBB\xBF', 'binary'), Buffer.from(content)]);
        return new Promise((resolve, reject) => {
                fs.writeFile("runtime/" + filename, data, function (err) {
                    if (err) {
                        resolve('');
                    } else {
                        resolve(filename);
                    }
                })
            })
            // return data;
        }

    }

    module.exports = Download

而後在action裏查出要生成的excel列表的內容

//生成excel
    '/npi/excel': {
        get: async (ctx, next) => {
            let
                query = ctx.query,
                charityId = query.charityId || 0,
                createTimeStart = query.createTimeStart || '',
                createTimeEnd = query.createTimeEnd || '',
                project_title = query.projectTitle || '',
                registered_no = query.registeredNo || '',
                progress_status = query.progressStatus || '',
                promoter_name = query.promoterName || '',
                down = new Download(ctx);

            let list, model;


            model = Model.tblGyProjectInfo().where('status', 'ACTIVE');
            if (charityId) {
                model.where('charity_id', charityId);
            }
            if (project_title) {
                model.where('project_title', project_title);
            }
            if (registered_no) {
                model.where('registered_no', registered_no);
            }
            if (progress_status) {
                model.where('progress_status', progress_status);
            }
            if (promoter_name) {
                model.where('promoter_name', promoter_name);
            }
            if (createTimeStart) {
                model.where('create_time >=', createTimeStart);
            }
            if (createTimeStart) {
                model.where('create_time <=', createTimeEnd);
            }
            list = await model.getAll();

            list = (list || []).map(function (row) {
                row.create_time = _.date(row.create_time);
                row.start_date = _.date(row.start_date);
                row.end_date = _.date(row.end_date);
                return row;
            });

            for (var i = 0; i < list.length; i++) {
                down.newRow();
                down.addCol(list[i].registered_no).addCol(list[i].project_title).addCol(list[i].progress_status)
                down.addCol(list[i].create_time).addCol(list[i].start_date).addCol(list[i].end_date);
            };
            let data = await down.save("project.xls");
            return _.succ({
                data: data
            })
        }
    },

須要在根目錄建立一個runtime文件夾來存儲生成的excel表格

而後在前端的ajax請求裏這麼寫

downloadExcel() {
                let data = {
                    ...this.search,
                };
                this.$get('/npi/excel', data, function (res) {
                    if (!res.status) {
                        this.$message.error('下載失敗！');
                        return;
                    }
                    window.location.href = 'http://172.18.163.247:13003/' + res.data.data;
                    this.$message.success('下載成功！');
                }.bind(this));

            },

window.location.href = 的前半部分是網絡地址和端口號，後面的res.data.data 是server端傳過來的，文件的名字

 

還要在index.js里加上這兩句話

const static = require('koa-static');

app.use(static(__dirname + '/runtime'));

這句話是保證runtime就是在根目錄下