应用场景：由前端处理表单内容加入表格的增删改查（页面处理，不需调接口）

// 点击"新增"按钮(置空表单内容)
const addFn = () => {
  title.value = '新增'
  formDataDialog.value = getformDataDialog() //表单内容置空
  dialogVisible.value = true
}
// 点击"修改"按钮(回显赋值)
const editFn = (scope) => {
  title.value = '修改'
  indexData.value = scope.$index
  formDataDialog.value = scope.row //赋值
  dialogVisible.value = true
}
// 点击"查看"按钮(赋值)
const searchFn = (scope) => {
  title.value = '查看'
  formDataDialog.value = scope.row //赋值
  dialogVisible.value = true
}
// 点击"删除"按钮(前端删除)
const deleteFn = (scope) => {
  ElMessageBox.confirm('是否确定要删除这条数据?', '提示', {
    confirmButtonText: '确定',
    cancelButtonText: '取消',
    type: 'warning'
  }).then(async () => {
    tableData.value.splice(scope.$index, 1) //删除
    ElMessage.success('删除成功！')
  })
}

// 弹出框-提交（修改/新增）
const submitDialogItem = () => {
   if (title.value == '修改') {
     tableData.value.splice(indexData.value, 1, JSON.parse(JSON.stringify(formDataDialog.value)))
     dialogVisible.value = false
   } else {
     //新增
     tableData.value.push(formDataDialog.value)
     dialogVisible.value = false
  }
}