是更好地使用[使用]语句在C＃或[处理]的方法？这是否适用于外部（COM）对象？ [英] Is it better to use the [using] statement in C# or the [dispose] method? Does this apply to external (COM) objects?

问题描述

当一个对象完成了什么是好，使用指令，或者处置指令？

What is better, the using directive, or the dispose directive when finished with an object?

 using(FileStream fileStream = new FileStream(
            "logs/myapp.log",
            FileMode.Open,
            FileAccess.Read,
            FileShare.ReadWrite))
        {
            using(StreamReader streamReader = new StreamReader(fileStream))
            {
                this.textBoxLogs.Text = streamReader.ReadToEnd();
            }
        }

在另一方面，当我处理System.Net.Mail，有人告诉我，我需要的对象，以Dispose（）方法来释放任何杂散锁。

On the other hand, when I'm dealing with System.Net.Mail, I'm told I need to Dispose() of the object to release any stray locks.

有没有一致的指导？我怎么知道什么是更适合于给定对象的给定的情况？

Is there any consistent guidance? How do I tell what is more appropriate in a given situation for a given object?

推荐答案

有没有原因，我能想到的手动调用的Dispose（），比另一种实现其他对的Dispose（）（例如，在一类，你已经创建了一个工具的IDisposable ）时，你可以用一个对象在使用块。在使用块使对象的创建和处理在一个try / catch / finally块为 pretty的多 gaurantee该对象将正确处置。

There's no reason that I can think of to manually call Dispose(), other than in another implementation of Dispose() (for example in a class you've created that implements IDisposable) when you can wrap an object in a using block. The using block puts the creation and disposal of the object in a try/catch/finally block to pretty much gaurantee that the object will be disposed of correctly.

的编译器是比我更可靠。或者你。 =）

MSDN文档的 using语句并呼叫在那里你可以得到在 C＃语言规范在这里你可以查看第8.13节using语句 （至少在V4.0中引用它的8.13），让using语句的COM prehensive解释和如何使用它。第五段给出了以下内容：

MSDN documents the using statement and calls out where you can obtain the C# language specification where you can review section 8.13 "The using statement" (at least in the v4.0 reference it's 8.13) that gives a comprehensive explanation of the using statement and how to use it. The fifth paragraph gives the following:

using语句被翻译成   三个部分：获取，使用和   处置。资源的用法   隐式的try语句   它包括一个finally从句。本   最后条款处置的   资源。如果空资源   收购了，那么没有调用Dispose是   制成，并且不会引发任何异常。

A using statement is translated into three parts: acquisition, usage, and disposal. Usage of the resource is implicitly enclosed in a try statement that includes a finally clause. This finally clause disposes of the resource. If a null resource is acquired, then no call to Dispose is made, and no exception is thrown.

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