若依前后端分离版导入功能

1、添加导入按钮事件

<el-col :span="1.5">
  <el-button
    type="info"
    plain
    icon="el-icon-upload2"
    size="mini"
    @click="handleImport"
    v-hasPermi="['system:user:import']"
  >导入</el-button>
</el-col>

2、添加前端下载弹出框

<!-- 用户导入对话框 -->
<el-dialog :title="upload.title" :visible.sync="upload.open" width="400px" append-to-body>
  <el-upload
    ref="upload"
    :limit="1"
    accept=".xlsx, .xls"
    :headers="upload.headers"
    :action="upload.url + '?updateSupport=' + upload.updateSupport"
    :disabled="upload.isUploading"
    :on-progress="handleFileUploadProgress"
    :on-success="handleFileSuccess"
    :auto-upload="false"
    drag
  >
    <i class="el-icon-upload"></i>
    <div class="el-upload__text">将文件拖到此处，或<em>点击上传</em></div>
    <div class="el-upload__tip text-center" slot="tip">
      <div class="el-upload__tip" slot="tip">
        <el-checkbox v-model="upload.updateSupport" /> 是否更新已经存在的用户数据
      </div>
      <span>仅允许导入xls、xlsx格式文件。</span>
      <el-link type="primary" :underline="false" style="font-size:12px;vertical-align: baseline;" @click="importTemplate">下载模板</el-link>
    </div>
  </el-upload>
  <div slot="footer" class="dialog-footer">
    <el-button type="primary" @click="submitFileForm">确 定</el-button>
    <el-button @click="upload.open = false">取 消</el-button>
  </div>
</el-dialog>

3、前端调用方法

//导入模板接口importTemplate
import { importTemplate } from "@/api/system/student";
import { getToken } from "@/utils/auth";

// 用户导入参数
upload: {
  // 是否显示弹出层（用户导入）
  open: false,
  // 弹出层标题（用户导入）
  title: "",
  // 是否禁用上传
  isUploading: false,
  // 是否更新已经存在的用户数据
  updateSupport: 1,
  // 设置上传的请求头部
  headers: { Authorization: "Bearer " + getToken() },
  // 上传的地址
  url: process.env.VUE_APP_BASE_API + "/system/student/importData"
},

/** 导入按钮操作 */
handleImport() {
    this.upload.title = "用户导入";
    this.upload.open = true;
},
/** 下载模板操作 */
importTemplate() {
    const queryParams = this.queryParams;
    this.$modal.confirm('是否确认导出模板?',"警告",{
        confirmButtonText: "确定",
        cancelButtonText: "取消",
        type: "warning"
    }).then(() => {
        this.loading = true;
        console.log(importTemplate(queryParams));
        return importTemplate(queryParams);
    }).then(response => {
        console.log(response);
        this.$download.name(response.msg);
        this.loading = false;
    }).catch(() => {});
},
// 文件上传中处理
handleFileUploadProgress(event, file, fileList) {
     this.upload.isUploading = true;
},
// 文件上传成功处理
handleFileSuccess(response, file, fileList) {
    this.upload.open = false;
    this.upload.isUploading = false;
    this.$refs.upload.clearFiles();
    this.$alert(response.msg, "导入结果", { dangerouslyUseHTMLString: true });
    this.getList();
},
// 提交上传文件
submitFileForm() {
    this.$refs.upload.submit();
}

4、在实体变量上加上@Excel注解，默认为导入导出，也可以单独设置仅导入Type.IMPORT,导入数据的时候需要将字段上的readConverterExp去掉，要不然导入不了数据。导出的时候需要的话可以加上，用处是，例：0 = 男

/** 编号 */
@Excel(name = "学生序号", prompt = "学生编号")
private Long studentId;

/** 学生名称 */
@Excel(name = "学生名称")
private String studentName;

/** 年龄 */
@Excel(name = "年龄")
private Long studentAge;

/** 爱好（0代码 1音乐 2电影） */
@Excel(name = "爱好", readConverterExp = "0=代码,1=音乐,2=电影")
private String studentHobby;

/** 性别（0男 1女 2未知） */
@Excel(name = "性别", readConverterExp = "0=男,1=女,2=未知")
private Long studentSex;

/** 状态（0正常 1停用） */
@Excel(name = "状态", readConverterExp = "0=正常,1=停用")
private Long studentStatus;

/** 生日 */
@JsonFormat(pattern = "yyyy-MM-dd")
@Excel(name = "生日", width = 30, dateFormat = "yyyy-MM-dd")
private Date studentBirthday;

5、在Controller添加导入方法，下载模板方法，updateSupport属性为是否存在则覆盖（可选）

/**
 * 导出模板
 */
@GetMapping("/importTemplate")
public AjaxResult importTemplate(){
    ExcelUtil<SysStudent> util = new ExcelUtil<>(SysStudent.class);
    return util.importTemplateExcel("学生信息");
}

/**
 * 导入数据
 */
@Log(title = "学生管理", businessType = BusinessType.IMPORT)
@PreAuthorize("@ss.hasPermi('system:student:import')")
@PostMapping("/importData")
public AjaxResult importData(MultipartFile file, boolean updateSupport) throws Exception {
    ExcelUtil<SysStudent> util = new ExcelUtil<>(SysStudent.class);
    List<SysStudent> studentList = util.importExcel(file.getInputStream());
    System.out.println(studentList);
    String operName = getUsername();
    String message = sysStudentService.importStudent(studentList,updateSupport,operName);
    return AjaxResult.success(message);
}

导入sysStudentService.importStudent(studentList,updateSupport,operName);serviceImpl层实现代码：

/**
 * 导入学生数据
 *
 * @param studentList       学生数据列表
 * @param isUpdateSupport   是否支持更新,如果已存在,则进行更新数据
 * @param operName      操作用户
 * @return  结果
 */
@Override
public String importStudent(List<SysStudent> studentList, Boolean isUpdateSupport, String operName) {
    if (StringUtils.isNull(studentList) || studentList.size() == 0)
    {
        throw new ServiceException("导入用户数据不能为空！");
    }
    int successNum = 0;
    int failureNum = 0;
    StringBuilder successMsg = new StringBuilder();
    StringBuilder failureMsg = new StringBuilder();
    for (SysStudent student : studentList)
    {
        try
        {
            // 验证是否存在这个用户
            SysStudent u = sysStudentMapper.selectUserByStudentName(student.getStudentName());
            if (StringUtils.isNull(u))
            {
                this.insertSysStudent(student);
                successNum++;
                successMsg.append("<br/>" + successNum + "、账号 " + student.getStudentName() + " 导入成功");
            }
            else if (isUpdateSupport)
            {
                student.setUpdateBy(operName);
                this.updateSysStudentByName(student);
                successNum++;
                successMsg.append("<br/>" + successNum + "、账号 " + student.getStudentName() + " 更新成功");
            }
            else
            {
                failureNum++;
                failureMsg.append("<br/>" + failureNum + "、账号 " + student.getStudentName() + " 已存在");
            }
        }
        catch (Exception e)
        {
            failureNum++;
            String msg = "<br/>" + failureNum + "、账号 " + student.getStudentName() + " 导入失败：";
            failureMsg.append(msg + e.getMessage());
            log.error(msg, e);
        }
    }
    if (failureNum > 0)
    {
        failureMsg.insert(0, "很抱歉，导入失败！共 " + failureNum + " 条数据格式不正确，错误如下：");
        throw new ServiceException(failureMsg.toString());
    }
    else
    {
        successMsg.insert(0, "恭喜您，数据已全部导入成功！共 " + successNum + " 条，数据如下：");
    }
    return successMsg.toString();
}