1

server_admin/src/views/Datasets.vue

@@ -91,6 +91,15 @@ function onCoverChange(file, fileList) {
   if (coverFile.value) coverDeleted.value = false
 }
 
+// 已有一张封面时仍选择新文件（如相册多选触发 on-exceed）：替换为最后一张，保持单张语义
+function onCoverExceed(files) {
+  const last = files[files.length - 1]
+  coverFileList.value = [{ name: last.name, raw: last, url: URL.createObjectURL(last), status: 'ready' }]
+  coverFile.value = last
+  coverDeleted.value = false
+  ElMessage.info('封面仅支持一张，已替换为最后选择的图片')
+}
+
 // 删除项：删服务端已有封面（无 raw）→ 标记待删除；删新选文件且列表清空 → 同样按删除处理（服务端旧封面仍在）
 function onCoverRemove(file) {
   coverFile.value = null
@@ -336,8 +345,10 @@ onBeforeUnmount(() => {
               :auto-upload="false"
               accept=".jpg,.jpeg,.png"
               list-type="picture-card"
+              :limit="1"
               :on-change="onCoverChange"
               :on-remove="onCoverRemove"
+              :on-exceed="onCoverExceed"
             >
               <div v-if="coverFileList.length === 0" class="upload-tile">
                 <el-icon :size="22"><Plus /></el-icon>