（轉） C#中使用throw和throw ex拋出異常的區別

<div id="cnblogs_post_body" class="blogpost-body">   一般，咱們使用try/catch/finally語句塊來捕獲異常，就像在<a href="http://www.cnblogs.com/darrenji/p/3965443.html">這裏</a>說的。在拋出異常的時候，使用throw和throw ex有什麼區別呢？ 假設，按以下的方式調用幾個方法：   →在Main方法中調用Method1方法，try/catch捕獲異常 →在Method1方法中調用Method2方法，try/catch捕獲異常 →在Method2方法中故意拋出異常，try/catch捕獲異常   使用throw拋出異常  <pre style="overflow: auto; border-top: #cecece 1px solid; border-right: #cecece 1px solid; border-bottom: #cecece 1px solid; padding-bottom: 5px; padding-top: 5px; padding-left: 5px; min-height: 40px; border-left: #cecece 1px solid; padding-right: 5px; background-color: #f0f0f0"><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> static void Main(string[] args) </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> try </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> Method1(); </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> catch (Exception ex) </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> Console.WriteLine(ex.StackTrace.ToString()); </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"></pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> Console.ReadKey(); </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"></pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> static void Method1() </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> try </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> Method2(); </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> catch (Exception ex) </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> throw; </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"></pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> static void Method2() </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> try </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> throw new Exception("來自方法2的異常"); </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> catch (Exception ex) </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> throw; </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"></pre></pre>   <a href="http://images0.cnblogs.com/blog/417212/201505/221133324006560.png"><img title="1" style="border-top: 0px; border-right: 0px; background-image: none; border-bottom: 0px; padding-top: 0px; padding-left: 0px; border-left: 0px; display: inline; padding-right: 0px" border="0" alt="1" src="https://images0.cnblogs.com/blog/417212/201505/221133330251918.png" width="648" height="127"></a> 能夠看到，使用throw拋異常，把發生在Method2方法、Method1方法和Main方法中的異常所有拋了出來。 使用throw ex拋出異常   如今，在Method1方法中，使用throw ex拋出異常。 <pre style="overflow: auto; border-top: #cecece 1px solid; border-right: #cecece 1px solid; border-bottom: #cecece 1px solid; padding-bottom: 5px; padding-top: 5px; padding-left: 5px; min-height: 40px; border-left: #cecece 1px solid; padding-right: 5px; background-color: #f0f0f0"><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> static void Method1() </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> try </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> Method2(); </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> catch (Exception ex) </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> { </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> throw ex; </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> } </pre><pre style="font-size: 10px; font-family: consolas,'Courier New',courier,monospace; width: 100%; margin: 0em; background-color: #f0f0f0"> }</pre></pre>   <a href="http://images0.cnblogs.com/blog/417212/201505/221133335724018.png"><img title="2" style="border-top: 0px; border-right: 0px; background-image: none; border-bottom: 0px; padding-top: 0px; padding-left: 0px; border-left: 0px; display: inline; padding-right: 0px" border="0" alt="2" src="https://images0.cnblogs.com/blog/417212/201505/221133344007904.png" width="650" height="83"></a>     可見，使用throw ex拋異常，只會把Method1方法和Main方法中的異常拋出來。   <blockquote> 總結：若是想獲取最完整的StackTrace信息，使用throw拋出異常，從中能夠知道異常到底來自哪一個方法。</blockquote></div>html

**轉自: C#中使用throw和throw ex拋出異常的區別 - Darren Ji - 博客園 http://www.cnblogs.com/darrenji/p/4521886.html **post