c# – Azure october 2012 sdk – 如何删除表实体而不先检索它?
发布时间:2020-12-15 18:07:03 所属栏目:百科 来源:网络整理
导读:在以前的版本中,我们可以在不知道它是否存在的情况下删除实体. svc = new TestContext();item = new TestEntity("item2pk","item2rk");svc.AttachTo("TestTable",item,"*");svc.DeleteObject(item);svc.SaveChanges(); (source) 新的TableOperations没有此语
在以前的版本中,我们可以在不知道它是否存在的情况下删除实体.
svc = new TestContext(); item = new TestEntity("item2pk","item2rk"); svc.AttachTo("TestTable",item,"*"); svc.DeleteObject(item); svc.SaveChanges(); (source) 新的TableOperations没有此语法.我必须使用这种旧方法还是有办法?我想保持一致,因为现在我的所有代码都使用了第2版的新类. 编辑:标题具有误导性 解决方法
您需要使用TableOperation.Delete:
var storageAccount = CloudStorageAccount.DevelopmentStorageAccount; var table = storageAccount.CreateCloudTableClient() .GetTableReference("tempTable"); table.CreateIfNotExists(); // Add item. table.Execute(TableOperation.Insert(new TableEntity("MyItems","123"))); // Load items. var items = table.ExecuteQuery(new TableQuery<TableEntity>()); foreach (var item in items) { Console.WriteLine(item.PartitionKey + " - " + item.RowKey); } // Delete item (the ETAG is required here!). table.Execute(TableOperation.Delete(new TableEntity("MyItems","123") { ETag = "*" })); 删除仅适用于存在的实体.即使旧客户端具有ContinueOnError选项,它也与批处理操作(as explained here)不兼容. 成功批量删除的唯一方法是,如果您不知道实体存在它,则首先添加它们(或者如果它们已经存在则替换它们): var ensureItemsBatch = new TableBatchOperation(); ensureItemsBatch.InsertOrReplace(new MyEntity("MyItems","123") { Active = false }); ensureItemsBatch.InsertOrReplace(new MyEntity("MyItems","456") { Active = false }); ensureItemsBatch.InsertOrReplace(new MyEntity("MyItems","789") { Active = false }); table.ExecuteBatch(ensureItemsBatch); var deleteItemsBatch = new TableBatchOperation(); deleteItemsBatch.Delete(new MyEntity("MyItems","123") { ETag = "*" }); deleteItemsBatch.Delete(new MyEntity("MyItems","456") { ETag = "*" }); deleteItemsBatch.Delete(new MyEntity("MyItems","789") { ETag = "*" }); table.ExecuteBatch(deleteItemsBatch); (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |