#什麼是Code Snippet

從字面來看是程式碼片段，如果已經寫程式一段時間應該都有用到過，例如在Visual Studio打上Switch後按兩下Tab自動產生的程式碼就是Code Snippet功能做出來的。

所以將常常重複寫的程式碼做成Code Snippet是一件很方便的事情

#如何自訂

因為寫單元測試常常需要寫3A原則,所以把它做成Code Snippet就可以重用。

//// arrange
var sut = GetSystemUnderTest();
var expected = true;

//// act
var actual = sut.DoSomething();

//// assert

建立3A Pattern.snippet的檔案

打開一個記事本命名成3A Pattern，然後副檔名儲存成.snippet

撰寫內容

<?xml version="1.0" encoding="utf-8"?>
<CodeSnippets xmlns="http://schemas.microsoft.com/VisualStudio/2005/CodeSnippet">
  <CodeSnippet Format="1.0.0">
    <Header>
      <SnippetTypes>
        <SnippetType>Expansion</SnippetType>
        <SnippetType>SurroundsWith</SnippetType>
      </SnippetTypes>
      <Title>你的Code Snippet名稱</Title>
      <Author>Steven</Author>
      <Description>
      </Description>
      <HelpUrl>
      </HelpUrl>
      <Shortcut>你想要呼叫時的代碼</Shortcut>
    </Header>
    <Snippet>
      <Declarations>
        <Literal Editable="true">
          <ID>變數ID</ID>
          <ToolTip>變數描述</ToolTip>
          <Default>預設值</Default>
          <Function>
          </Function>
        </Literal>
      </Declarations>
      <Code Language="csharp" Delimiter="$"><![CDATA[
		......
         放入程式碼的地方        
		......
        ]]></Code>
    </Snippet>
  </CodeSnippet>
</CodeSnippets>

依據上面的Template,將3A Pattern Code Snippet改成

<?xml version="1.0" encoding="utf-8"?>
<CodeSnippets xmlns="http://schemas.microsoft.com/VisualStudio/2005/CodeSnippet">
  <CodeSnippet Format="1.0.0">
    <Header>
      <SnippetTypes>
        <SnippetType>Expansion</SnippetType>
        <SnippetType>SurroundsWith</SnippetType>
      </SnippetTypes>
      <Title>3A Pattern</Title>
      <Author>Steven</Author>
      <Description>
      </Description>
      <HelpUrl>
      </HelpUrl>
      <Shortcut>aaa</Shortcut>
    </Header>
    <Snippet>
      <Declarations>
        <Literal Editable="true">
          <ID>expected</ID>
          <ToolTip>expected</ToolTip>
          <Default>true</Default>
          <Function>
          </Function>
        </Literal>
        <Literal Editable="true">
          <ID>DoSomthing</ID>
          <ToolTip>DoSomthing</ToolTip>
          <Default>DoSomething()</Default>
          <Function>
          </Function>
        </Literal>
      </Declarations>
      <Code Language="csharp" Delimiter="$"><![CDATA[
        //// arrange
        var sut = GetSystemUnderTest();
        var expected = $expected$;
        
        //// act
        var actual = sut.$DoSomthing$;
        
        //// assert
        ]]></Code>
    </Snippet>
  </CodeSnippet>
</CodeSnippets>