vue 限制上传图片的宽高（基于iviewUI）

1、需要效果

2、vue代码

<Upload
            multiple
            ref="uploadContent"
            :on-success="handleSuccess"
            :on-error="handleError"
            :format="['jpg','jpeg','png']"
            :on-format-error="handleFormatError"
            :show-upload-list="false"
            :action="uploadUrl"
            :before-upload="detailBeforeUpload"
            style="float: right">
              <Button class="uploadFiles" >上传文件</Button>
            </Upload>       

3、方法

detailBeforeUpload(file) {
    return this.checkImageWH(file, 1280, 90);
},
checkImageWH(file, width, height) {
        let self = this;
        return new Promise(function (resolve, reject) {
          let filereader = new FileReader();
          filereader.onload = e => {
            let src = e.target.result;
            const image = new Image();
            image.onload = function () {
              if (width && this.width != width) {
                self.$Message.error('请上传宽为' + width + "px的图片");
                reject();
              } else if (height && this.height != height) {
                self.$Message.error('请上传宽为' + height + "px的图片");
                reject();
              } else {
                resolve();
              }
            };
            image.onerror = reject;
            image.src = src;
          };
          filereader.readAsDataURL(file);
        });
},