若依自带vue-cropper上传图片（可旋转、缩放）

2024.4.4今天我学习了如何使用若依的vue-cropper上传图片组件，在工作中遇到一个需求，需要对上传的图片进行旋转的操作，然后我先找到el-upload组件，使用之后发现它有一个自动上传和非自动上传的功能，是不是就可以通过非自动上传的功能然后跳一个弹窗，在弹窗里面进行操作再上传。

一、用el-upload

在使用非自动上传之后用on-change事件来触发一个弹窗，把上传的图片先放大显示，然后下面放一个左右旋转的按钮，通过ref this.$ref.xxx.style.transform修改样式进行旋转，但是这样只能单纯的旋转图片，不能把旋转之后的图片保存下来。

官方地址：

Element - The world's most popular Vue UI framework

二、用vue-cropper

后来百度找到若依有自带上传图片旋转的方法。

官方地址：若依管理系统

官方代码地址：ruoyi-ui/src/views/system/user/profile/userAvatar.vue · 若依/RuoYi-Vue - Gitee.com

效果如下：

完整代码如下：

<template>
  <div>
    <div class="user-info-head" @click="editCropper()"><img v-bind:src="options.img" title="点击上传头像" class="img-circle img-lg" /></div>
    <el-dialog :title="title" :visible.sync="open" width="800px" append-to-body @opened="modalOpened"  @close="closeDialog">
      <el-row>
        <el-col :xs="24" :md="12" :style="{height: '350px'}">
          <vue-cropper
              ref="cropper"
              :img="options.img"
              :info="true"
              :autoCrop="options.autoCrop"
              :autoCropWidth="options.autoCropWidth"
              :autoCropHeight="options.autoCropHeight"
              :fixedBox="options.fixedBox"
              :outputType="options.outputType"
              @realTime="realTime"
              v-if="visible"
          />
        </el-col>
        <el-col :xs="24" :md="12" :style="{height: '350px'}">
          <div class="avatar-upload-preview">
            <img :src="previews.url" :style="previews.img" />
          </div>
        </el-col>
      </el-row>
      <br />
      <el-row>
        <el-col :lg="2" :sm="3" :xs="3">
          <el-upload action="#" :http-request="requestUpload" :show-file-list="false" :before-upload="beforeUpload">
            <el-button size="small">
              选择
              <i class="el-icon-upload el-icon--right"></i>
            </el-button>
          </el-upload>
        </el-col>
        <el-col :lg="{span: 1, offset: 2}" :sm="2" :xs="2">
          <el-button icon="el-icon-plus" size="small" @click="changeScale(1)"></el-button>
        </el-col>
        <el-col :lg="{span: 1, offset: 1}" :sm="2" :xs="2">
          <el-button icon="el-icon-minus" size="small" @click="changeScale(-1)"></el-button>
        </el-col>
        <el-col :lg="{span: 1, offset: 1}" :sm="2" :xs="2">
          <el-button icon="el-icon-refresh-left" size="small" @click="rotateLeft()"></el-button>
        </el-col>
        <el-col :lg="{span: 1, offset: 1}" :sm="2" :xs="2">
          <el-button icon="el-icon-refresh-right" size="small" @click="rotateRight()"></el-button>
        </el-col>
        <el-col :lg="{span: 2, offset: 6}" :sm="2" :xs="2">
          <el-button type="primary" size="small" @click="uploadImg()">提 交</el-button>
        </el-col>
      </el-row>
    </el-dialog>
  </div>
</template>

<script>
import store from "@/store";
import { VueCropper } from "vue-cropper";
import { uploadAvatar } from "@/api/system/user";
import { debounce } from '@/utils'

export default {
  components: { VueCropper },
  data() {
    return {
      // 是否显示弹出层
      open: false,
      // 是否显示cropper
      visible: false,
      // 弹出层标题
      title: "修改头像",
      options: {
        img: store.getters.avatar,  //裁剪图片的地址
        autoCrop: true,             // 是否默认生成截图框
        autoCropWidth: 200,         // 默认生成截图框宽度
        autoCropHeight: 200,        // 默认生成截图框高度
        fixedBox: true,             // 固定截图框大小 不允许改变
        outputType:"png",           // 默认生成截图为PNG格式
        filename: 'avatar'          // 文件名称
      },
      previews: {},
      resizeHandler: null
    };
  },
  methods: {
    // 编辑头像
    editCropper() {
      this.open = true;
    },
    // 打开弹出层结束时的回调
    modalOpened() {
      this.visible = true;
      if (!this.resizeHandler) {
        this.resizeHandler = debounce(() => {
          this.refresh()
        }, 100)
      }
      window.addEventListener("resize", this.resizeHandler)
    },
    // 刷新组件
    refresh() {
      this.$refs.cropper.refresh();
    },
    // 覆盖默认的上传行为
    requestUpload() {
    },
    // 向左旋转
    rotateLeft() {
      this.$refs.cropper.rotateLeft();
    },
    // 向右旋转
    rotateRight() {
      this.$refs.cropper.rotateRight();
    },
    // 图片缩放
    changeScale(num) {
      num = num || 1;
      this.$refs.cropper.changeScale(num);
    },
    // 上传预处理
    beforeUpload(file) {
      if (file.type.indexOf("image/") == -1) {
        this.$modal.msgError("文件格式错误，请上传图片类型,如：JPG，PNG后缀的文件。");
      } else {
        const reader = new FileReader();
        reader.readAsDataURL(file);
        reader.onload = () => {
          this.options.img = reader.result;
          this.options.filename = file.name;
        };
      }
    },
    // 上传图片
    uploadImg() {
      this.$refs.cropper.getCropBlob(data => {
        let formData = new FormData();
        formData.append("avatarfile", data, this.options.filename);
        uploadAvatar(formData).then(response => {
          this.open = false;
          this.options.img = process.env.VUE_APP_BASE_API + response.imgUrl;
          store.commit('SET_AVATAR', this.options.img);
          this.$modal.msgSuccess("修改成功");
          this.visible = false;
        });
      });
    },
    // 实时预览
    realTime(data) {
      this.previews = data;
    },
    // 关闭窗口
    closeDialog() {
      this.options.img = store.getters.avatar
      this.visible = false;
      window.removeEventListener("resize", this.resizeHandler)
    }
  }
};
</script>
<style scoped lang="scss">
.user-info-head {
  position: relative;
  display: inline-block;
  height: 120px;
}

.user-info-head:hover:after {
  content: '+';
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  color: #eee;
  background: rgba(0, 0, 0, 0.5);
  font-size: 24px;
  font-style: normal;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  cursor: pointer;
  line-height: 110px;
  border-radius: 50%;
}
</style>