{"id":50,"date":"2008-02-09T20:28:08","date_gmt":"2008-02-09T20:28:08","guid":{"rendered":""},"modified":"2008-02-09T20:28:08","modified_gmt":"2008-02-09T20:28:08","slug":"50","status":"publish","type":"post","link":"https:\/\/www.poloo.org\/?p=50","title":{"rendered":"\u4f7f\u7528 ref \u548c out \u4f20\u9012\u6570\u7ec4"},"content":{"rendered":"

c#\u5b66\u4e60\u4f53\u4f1a:\u4f7f\u7528 ref \u548c out \u4f20\u9012\u6570\u7ec4
1\u3001\u4e0e\u6240\u6709\u7684 out \u53c2\u6570\u4e00\u6837\uff0c\u5728\u4f7f\u7528\u6570\u7ec4\u7c7b\u578b\u7684 out \u53c2\u6570\u524d\u5fc5\u987b\u5148\u4e3a\u5176\u8d4b\u503c\uff0c\u5373\u5fc5\u987b\u7531\u63a5\u53d7\u65b9\u4e3a\u5176\u8d4b\u503c\u3002\u4f8b\u5982\uff1a<\/p>\n

public static void MyMethod(out int[] arr)
{
   arr = new int[10];   \/\/ \u6570\u7ec4arr\u7684\u660e\u786e\u59d4\u6d3e
}
<\/code>
2\u3001\u4e0e\u6240\u6709\u7684 ref \u53c2\u6570\u4e00\u6837\uff0c\u6570\u7ec4\u7c7b\u578b\u7684 ref \u53c2\u6570\u5fc5\u987b\u7531\u8c03\u7528\u65b9\u660e\u786e\u8d4b\u503c\u3002\u56e0\u6b64\u4e0d\u9700\u8981\u7531\u63a5\u53d7\u65b9\u660e\u786e\u8d4b\u503c\u3002\u53ef\u4ee5\u5c06\u6570\u7ec4\u7c7b\u578b\u7684 ref \u53c2\u6570\u66f4\u6539\u4e3a\u8c03\u7528\u7684\u7ed3\u679c\u3002\u4f8b\u5982\uff0c\u53ef\u4ee5\u4e3a\u6570\u7ec4\u8d4b\u4ee5 null \u503c\uff0c\u6216\u5c06\u5176\u521d\u59cb\u5316\u4e3a\u53e6\u4e00\u4e2a\u6570\u7ec4\u3002\u4f8b\u5982\uff1a<\/p>\n

public static void MyMethod(ref int[] arr)
{
   arr = new int[10];   \/\/ arr\u521d\u59cb\u5316\u4e3a\u4e00\u4e2a\u65b0\u7684\u6570\u7ec4
}
<\/code>
\u4e0b\u9762\u7684\u4e24\u4e2a\u793a\u4f8b\u8bf4\u660e out \u548c ref \u5728\u5c06\u6570\u7ec4\u4f20\u9012\u7ed9\u65b9\u6cd5\u4e0a\u7684\u7528\u6cd5\u5dee\u5f02\u3002<\/p>\n

\u793a\u4f8b 1
\u5728\u6b64\u4f8b\u4e2d\uff0c\u5728\u8c03\u7528\u65b9\uff08Main \u65b9\u6cd5\uff09\u4e2d\u58f0\u660e\u6570\u7ec4 myArray\uff0c\u5e76\u5728 FillArray \u65b9\u6cd5\u4e2d\u521d\u59cb\u5316\u6b64\u6570\u7ec4\u3002\u7136\u540e\u5c06\u6570\u7ec4\u5143\u7d20\u8fd4\u56de\u8c03\u7528\u65b9\u5e76\u663e\u793a\u3002<\/p>\n

using System;
class TestOut
{
   static public void FillArray(out int[] myArray)
   {
      \/\/ \u521d\u59cb\u5316\u6570\u7ec4\uff08\u5fc5\u987b\uff09:
      myArray = new int[5] {1, 2, 3, 4, 5};
   }<\/p>\n

   static public void Main()
   {
      int[] myArray; \/\/ \u521d\u59cb\u5316\u6570\u7ec4(\u4e0d\u662f\u5fc5\u987b\u7684!)<\/p>\n

      \/\/ \u4f20\u9012\u6570\u7ec4\u7ed9\uff08\u4f7f\u7528out\u65b9\u5f0f\u7684\uff09\u8c03\u7528\u65b9:
      FillArray(out myArray);<\/p>\n

      \/\/ \u663e\u793a\u6570\u7ec4\u5143\u7d20
      Console.WriteLine(\"\u6570\u7ec4\u5143\u7d20\u662f:\");
      for (int i=0; i < myArray.Length; i++)
         Console.WriteLine(myArray[i]);
   }
}
<\/code>
\u8f93\u51fa
\u6570\u7ec4\u5143\u7d20\u662f:
1
2
3
4
5
\u793a\u4f8b 2
\u5728\u6b64\u4f8b\u4e2d\uff0c\u5728\u8c03\u7528\u65b9\uff08Main \u65b9\u6cd5\uff09\u4e2d\u521d\u59cb\u5316\u6570\u7ec4 myArray\uff0c\u5e76\u901a\u8fc7\u4f7f\u7528 ref \u53c2\u6570\u5c06\u5176\u4f20\u9012\u7ed9 FillArray \u65b9\u6cd5\u3002\u5728 FillArray \u65b9\u6cd5\u4e2d\u66f4\u65b0\u67d0\u4e9b\u6570\u7ec4\u5143\u7d20\u3002\u7136\u540e\u5c06\u6570\u7ec4\u5143\u7d20\u8fd4\u56de\u8c03\u7528\u65b9\u5e76\u663e\u793a\u3002<\/p>\n

using System;
class TestRef
{
   public static void FillArray(ref int[] arr)
   {
      \/\/ \u6839\u636e\u9700\u8981\u521b\u5efa\u4e00\u65b0\u7684\u6570\u7ec4(\u4e0d\u662f\u5fc5\u987b\u7684)
      if (arr == null)
         arr = new int[10];
      \/\/ \u5426\u5219\u586b\u5145\u6570\u7ec4\uff0c\u5c31\u53ef\u4ee5\u4e86
      arr[0] = 123;
      arr[4] = 1024;
   }<\/p>\n

   static public void Main ()
   {
      \/\/\u521d\u59cb\u5316\u6570\u7ec4:
      int[] myArray =     {1,2,3,4,5}; <\/p>\n

      \/\/ \u4f7f\u7528ref\u4f20\u9012\u6570\u7ec4:
      FillArray(ref myArray);<\/p>\n

      \/\/\u663e\u793a\u66f4\u65b0\u540e\u7684\u6570\u7ec4\u5143\u7d20:
      Console.WriteLine(\"\u6570\u7ec4\u5143\u7d20\u662f:\");
      for (int i = 0; i < myArray.Length; i++)
         Console.WriteLine(myArray[i]);
   }
}
<\/code>
\u8f93\u51fa
\u6570\u7ec4\u5143\u7d20\u662f:
123
2
3
4
1024<\/p>\n","protected":false},"excerpt":{"rendered":"

c#\u5b66\u4e60\u4f53\u4f1a:\u4f7f\u7528 ref \u548c out \u4f20\u9012\u6570\u7ec41\u3001\u4e0e\u6240\u6709\u7684 out...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13],"tags":[],"class_list":["post-50","post","type-post","status-publish","format-standard","hentry","category-NET"],"_links":{"self":[{"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/posts\/50","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.poloo.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=50"}],"version-history":[{"count":0,"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/posts\/50\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.poloo.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=50"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.poloo.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=50"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.poloo.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=50"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}