How to add the default image to element's table list?

the following code, added several times the default picture is not added, how to add the default picture? Then replace the default image

when the picture is loaded.
   <el-table-column label="" width="100%" >
          <template slot-scope="scope">
            <el-popover
              placement="right"
              title=""
              trigger="hover">
              <img :src="scope.row.cover" width="180px" height="250px" > //
              <img  slot="reference" :src="scope.row.cover" style="height: 80%"> //
            </el-popover>
          </template>
        </el-table-column>
Oct.27,2021

display the default picture first, and then replace the src of the default image with the actual picture to be displayed through js in the mounted hook of vue

Menu