Vue实现excel导出，不请求后端

原因是做出来的不符合需求，需要连接后端，又不想删掉，做个记录
1：先创建一个按钮

 <el-col :span="1.5">
            <el-button
              @click="exportExcel"
              size="mini"
              type="primary"
              icon="el-icon-download"
            >导出Excel</el-button>
</el-col>

2：先查看是XLSX的依赖，没有的话需要安装一下

npm install xlsx

安装的时候如果报错需要清理缓存，并把依赖包删掉重新安装
node_modules为项目中的依赖包

npm cache clean --force

//linux
rm -rf node_modules
//windows
Remove-Item -Recurse -Force node_modules

npm install

出现这个问题的话需要，重新编译node-sass
Found bindings for the following environments: - Windows 64-bit with Node.js 10.x This usually happens because your environment has changed since running npm install. Run npm rebuild node-sass to download the binding for your current environment.

npm rebuild node-sass

3：然后引入

<script>
import XLSX from 'xlsx';

4：添加导出方法

method:{
exportExcel() {
      // 导出Excel的方法
      if(this.list.length > 0){
      	//此处的this.list为列表的数据集合
        const data = this.list.map(item => {
          return {
            '列名1': item.数据名称,
            '列名2': item.数据名称,
            '列名3': item.数据名称,
            '列名4': item.数据名称
          };
        });
        const worksheet = XLSX.utils.json_to_sheet(data);
        const columnWidths = [
          { wch: 20 },  // 第一列宽度为20
          { wch: 15 },  // 第二列宽度为15
          { wch: 10 },  // 第三列宽度为10
          { wch: 15 }   // 第四列宽度为15
        ];
        worksheet['!cols'] = columnWidths;
        const workbook = {
          Sheets: { 'data': worksheet },
          SheetNames: ['data']
        };
        const excelBuffer = XLSX.write(workbook, { bookType: 'xlsx', type: 'buffer' });
        const blob = new Blob([excelBuffer], { type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8' });
        const filename = '文件名.xlsx';
        if (typeof navigator.msSaveBlob === 'function') {
          navigator.msSaveBlob(blob, filename);
        } else {
          const link = document.createElement('a');
          if (link.download !== undefined) {
            const url = URL.createObjectURL(blob);
            link.setAttribute('href', url);
            link.setAttribute('download', filename);
            link.style.visibility = 'hidden';
            document.body.appendChild(link);
            link.click();
            document.body.removeChild(link);
          }
        }
      }else{
        this.$message.error('暂无数据');
      }
    },
   }