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Springboot与vue实现文件导入方法具体介绍

作者:进击的Coders

文件导入时大多数项目无法回避的问题,这两天深入学习了文件导入,在这里进行记录,使用到的技术是Springboot+Vue,前端组件使用el-upload

一、Java后端使用MultipartFile

@PostMapping(value = "/upload")
    public String upload(@RequestParam("file") MultipartFile multipartFile) {
        return FileUploadUtil.upload(multipartFile);
    }

如果使用Springboot架构,直接使用MultipartFile工具即可,后端拿到MultipartFile对象之后,对其进一步处理就能拿到数据,或者存入数据库,或者保存到本地都可以。

二、Java后端直接从request中读取并转换为字符串

	Part importFile = request.getPart("file");
	InputStream inputstream = importFile.getInputStream();
	BufferedReader streamReader = new BufferedReader(new InputStreamReader(inputstream, "UTF-8"));
	StringBuilder stringBuilder = new StringBuilder();
	String inputStr;
	while ((inputStr = streamReader.readLine()) != null) {
	    stringBuilder.append(inputStr);
	}
	String s = stringBuilder.toString();

直接从request中读取需要使用Part类,从request中根据名称获取到part对象,然后再转换为流的形式,之后使用BufferedReader流读取器,逐行读取文件内容并添加到字符串构造器中,生成字符串。

三、Java后端直接从request中读取并存入本地文件

HttpServletRequest request = context.getRequest();
FileOutputStream fos = new FileOutputStream("C:\\Users\\Junhao\\Desktop\\import.json");
byte[] buffer = new byte[1024];
int len;
Part file = request.getPart("file");
InputStream inputstream = file.getInputStream();
while ((len = inputstream.read(buffer)) != -1){
    fos.write(buffer, 0, len);
}
fos.close();
inputstream.close();
String responseString = readInputStream(inputstream);
System.out.println(responseString);
BufferedReader streamReader = new BufferedReader(new InputStreamReader(inputstream, "UTF-8"));
StringBuilder stringBuilder = new StringBuilder();
String inputStr;
while ((inputStr = streamReader.readLine()) != null) {
    stringBuilder.append(inputStr);
}
String s = stringBuilder.toString();
Object parse = JSON.parse(s);

四、前端使用el-upload

由于要求在上传之前进行检验,然后根据检验的结果,对于冲突的实体,逐项选择覆盖已有实体,或者使用原来实体,这相对于单纯的文件上传,提高了难度

1.el-upload使用

   <el-dialog :title="upload.title" :visible.sync="upload.open" width="400px" append-to-body>
      <el-upload
        ref="upload"
        :limit="1"
        accept=".json"
        :headers="upload.headers"
        :action="upload.url"
        :disabled="upload.isUploading"
        :on-progress="handleFileUploadProgress"
        :on-success="handleFileSuccess"
        :on-change="handleChange"
        :before-remove="handleRemove"
        :auto-upload="false"
        drag
        :data="upload.uploadData"
      >
        <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" style="color:red" slot="tip">提示:仅允许导入“json”格式文件!</div>
      </el-upload>
        <div v-if="showImportCheckRes" style="margin-top: 8px">
          <el-tabs active-name="thing">
              <el-tab-pane name="thing" label="事物" style="height: 130px;" class="scrollbar">
                <el-scrollbar style="height: 100%">
                  <el-form label-position="left">
                    <div v-for="item in importCheckRes.existThings">
                      <el-form-item :label="item.code" label-width="160px">
                        <el-radio-group v-model="item.value">
                          <el-radio :label="0">暂不导入</el-radio>
                          <el-radio :label="1">覆盖</el-radio>
                        </el-radio-group>
                      </el-form-item>
                    </div>
                  </el-form>
                </el-scrollbar>
              </el-tab-pane>
              <el-tab-pane name="thingTemplate" label="事物模板" style="height: 130px;" class="scrollbar">
                <el-scrollbar style="height: 100%">
                  <el-form label-position="left">
                    <div v-for="item in importCheckRes.existThings">
                      <el-form-item :label="item.code" label-width="160px">
                        <el-radio-group v-model="item.value">
                          <el-radio :label="0">暂不导入</el-radio>
                          <el-radio :label="1">覆盖</el-radio>
                        </el-radio-group>
                      </el-form-item>
                    </div>
                  </el-form>
                </el-scrollbar>
              </el-tab-pane>
            <el-tab-pane name="dataModel" label="数据模型" style="height: 130px;" class="scrollbar">
              <el-scrollbar style="height: 100%">
                <el-form label-position="left">
                  <div v-for="item in importCheckRes.existDataModels">
                    <el-form-item :label="item.code" label-width="160px">
                      <el-radio-group v-model="item.value">
                        <el-radio :label="0">暂不导入</el-radio>
                        <el-radio :label="1">覆盖</el-radio>
                      </el-radio-group>
                    </el-form-item>
                  </div>
                </el-form>
              </el-scrollbar>
            </el-tab-pane>
            <el-tab-pane name="modelTag" label="模型标签" style="height: 130px;" class="scrollbar">
              <el-scrollbar style="height: 100%">
                <el-form label-position="left">
                  <div v-for="item in importCheckRes.existModelTags">
                    <el-form-item :label="item.code" label-width="160px">
                      <el-radio-group v-model="item.value">
                        <el-radio :label="0">暂不导入</el-radio>
                        <el-radio :label="1">覆盖</el-radio>
                      </el-radio-group>
                    </el-form-item>
                  </div>
                </el-form>
              </el-scrollbar>
            </el-tab-pane>
          </el-tabs>
        </div>
      <div slot="footer" class="dialog-footer">
        <el-button type="primary" @click="submitImport" size="mini">确 定</el-button>
        <el-button @click="upload.open = false" size="mini">取 消</el-button>
      </div>
    </el-dialog>

2.on-change验证文件内容

    handleChange(file){
      if (this.importStatus === 1){
        return;
      }
      let that = this
      let raw = file.raw
      const reader = new FileReader()
      reader.readAsText(raw, 'UTF-8')
      reader.onload=async function(evt){
        let dataJson = JSON.parse(evt.target.result)
        const Entities = dataJson.Entities
        const entityCode = {}
        Object.keys(Entities).forEach(item=>{
          const tempArray = []
          Object.values(Entities[item])[0].forEach(i=>{
            tempArray.push(i.code)
          })
          that.$set(entityCode, item, JSON.parse(JSON.stringify(tempArray)))
        })
        that.$nextTick(()=>{
          importCheck(entityCode).then(res=>{
            that.importCheckRes = res.data
            that.showImportCheckRes = true
          })
        })
      }
    },

在前端先解析文件,读取JSON数据,然后将要导入的code发送到后端,返回哪些是已有的,然后在前端进行覆盖或者暂不导入的选择,选择完成之后点击确定,携带选择的结果进行导入

    submitImport() {
      const tempJson = JSON.parse(JSON.stringify(this.importCheckRes))
      const importCheckRes = {}
      Object.keys(tempJson).forEach(item=>{
        const tempArray = []
        tempJson[item].forEach(i=>{
          if (i.value === 1){
            tempArray.push(i.code)
          }
        })
        this.$set(importCheckRes, item, tempArray);
      })
      this.$set(this.upload, 'uploadData', { importCheckRes: JSON.stringify(importCheckRes) })
      this.$nextTick(()=>{
        this.$refs.upload.submit()
      })
    },

3.效果截图

总结

这两天的项目中,学习了Java导出数据,其中遇到坑及总结如下:

到此这篇关于Springboot与vue实现文件导入方法具体介绍的文章就介绍到这了,更多相关Springboot文件导入内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家!

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