{"id":53,"date":"2026-03-30T09:20:40","date_gmt":"2026-03-30T01:20:40","guid":{"rendered":"https:\/\/blog.bandifee.com\/?p=53"},"modified":"2026-03-30T09:20:51","modified_gmt":"2026-03-30T01:20:51","slug":"%e6%b7%b1%e5%85%a5%e7%90%86%e8%a7%a3-c-%e4%b8%ad%e7%9a%84-span%ef%bc%9a%e9%ab%98%e6%80%a7%e8%83%bd%e7%bc%96%e7%a8%8b%e7%9a%84%e5%85%b3%e9%94%ae%e5%b7%a5%e5%85%b7","status":"publish","type":"post","link":"https:\/\/blog.bandifee.com\/index.php\/2026\/03\/30\/%e6%b7%b1%e5%85%a5%e7%90%86%e8%a7%a3-c-%e4%b8%ad%e7%9a%84-span%ef%bc%9a%e9%ab%98%e6%80%a7%e8%83%bd%e7%bc%96%e7%a8%8b%e7%9a%84%e5%85%b3%e9%94%ae%e5%b7%a5%e5%85%b7\/","title":{"rendered":"\u6df1\u5165\u7406\u89e3 C# \u4e2d\u7684 Span\uff1a\u9ad8\u6027\u80fd\u7f16\u7a0b\u7684\u5173\u952e\u5de5\u5177"},"content":{"rendered":"\n

\u5728\u73b0\u4ee3 C# \u5f00\u53d1\u4e2d\uff0c\u6027\u80fd\u4f18\u5316\u8d8a\u6765\u8d8a\u91cd\u8981\uff0c\u5c24\u5176\u662f\u5728\u5904\u7406\u5927\u91cf\u6570\u636e\u3001\u7b97\u6cd5\u4f18\u5316\uff08\u5982 DP\uff09\u3001\u6216\u9ad8\u9891\u8c03\u7528\u573a\u666f\u4e0b\u3002Span<T><\/code> \u6b63\u662f .NET \u4e3a\u89e3\u51b3\u201c\u9ad8\u6027\u80fd + \u5185\u5b58\u5b89\u5168\u201d\u95ee\u9898\u5f15\u5165\u7684\u6838\u5fc3\u5de5\u5177\u4e4b\u4e00\u3002<\/p>\n\n\n\n

\u672c\u6587\u5c06\u4ece \u6982\u5ff5\u3001\u539f\u7406\u3001\u4f7f\u7528\u65b9\u5f0f\u4ee5\u53ca\u9002\u7528\u573a\u666f<\/strong> \u5168\u9762\u8bb2\u89e3 Span<T><\/code>\u3002<\/p>\n\n\n\n

\n\n\n\n

\ud83e\udde0 \u4e00\u3001\u4ec0\u4e48\u662f Span<T>\uff1f<\/h2>\n\n\n\n

\u7b80\u5355\u6765\u8bf4\uff1a<\/p>\n\n\n\n

\n

Span<T> \u662f\u5bf9\u4e00\u6bb5\u8fde\u7eed\u5185\u5b58\u7684\u201c\u89c6\u56fe\uff08view\uff09\u201d\uff0c\u800c\u4e0d\u662f\u6570\u636e\u672c\u8eab\u3002<\/strong><\/p>\n<\/blockquote>\n\n\n\n

\u4f60\u53ef\u4ee5\u628a\u5b83\u7406\u89e3\u4e3a\uff1a<\/p>\n\n\n\n

Span<T> = \u6307\u9488 + \u957f\u5ea6<\/code><\/pre>\n\n\n\n
\u5b83\u5e76\u4e0d\u62e5\u6709\u6570\u636e\uff0c\u800c\u53ea\u662f\u201c\u5f15\u7528\u201d\u67d0\u4e00\u6bb5\u6570\u636e\u3002<\/p>\n\n\n\n
\n\n\n\n
\ud83d\udce6 \u4e8c\u3001\u4e00\u4e2a\u76f4\u89c2\u4f8b\u5b50<\/h2>\n\n\n\n
int[] arr = {1, 2, 3, 4, 5};\n\nSpan<int> span = arr;<\/code><\/pre>\n\n\n\n
\u6b64\u65f6\uff1a<\/p>\n\n\n\n
    \n
  • arr<\/code> \u2192 \u771f\u6b63\u7684\u6570\u636e\u5b58\u50a8<\/li>\n\n\n\n
  • span<\/code> \u2192 \u6307\u5411\u8fd9\u6bb5\u6570\u636e\u7684\u4e00\u4e2a\u7a97\u53e3<\/li>\n<\/ul>\n\n\n\n
    \n\n\n\n
    \ud83d\udd0d \u4e09\u3001Span \u7684\u6838\u5fc3\u7279\u6027<\/h2>\n\n\n\n
    1\ufe0f\u20e3 \u96f6\u62f7\u8d1d\uff08Zero Copy\uff09<\/h3>\n\n\n\n
    Span<int> s = arr;<\/code><\/pre>\n\n\n\n
    \u4e0d\u4f1a\u521b\u5efa\u65b0\u6570\u7ec4\uff0c\u53ea\u662f\u5f15\u7528\u539f\u59cb\u6570\u636e\u3002<\/p>\n\n\n\n
    \n\n\n\n
    2\ufe0f\u20e3 \u652f\u6301\u9ad8\u6548\u5207\u7247<\/h3>\n\n\n\n
    var sub = s[1..4];<\/code><\/pre>\n\n\n\n
    \u8fd9\u4e2a\u64cd\u4f5c\u4e0d\u4f1a\u590d\u5236\u6570\u636e\uff0c\u53ea\u662f\uff1a<\/p>\n\n\n\n
      \n
    • \u6539\u53d8\u8d77\u59cb\u6307\u9488<\/li>\n\n\n\n
    • \u4fee\u6539\u957f\u5ea6<\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n
      3\ufe0f\u20e3 \u4fee\u6539\u4f1a\u5f71\u54cd\u539f\u6570\u636e<\/h3>\n\n\n\n
      s[0] = 999;\nConsole.WriteLine(arr[0]); \/\/ \u8f93\u51fa 999<\/code><\/pre>\n\n\n\n
      \u56e0\u4e3a\u5b83\u4eec\u5171\u4eab\u540c\u4e00\u5757\u5185\u5b58\u3002<\/p>\n\n\n\n
      \n\n\n\n
      4\ufe0f\u20e3 \u9ad8\u6027\u80fd\uff08\u5173\u952e\u4f18\u52bf\uff09<\/h3>\n\n\n\n
        \n
      • \u274c \u65e0\u989d\u5916\u5185\u5b58\u5206\u914d<\/li>\n\n\n\n
      • \u274c \u65e0 GC \u538b\u529b<\/li>\n\n\n\n
      • \u2705 cache \u53cb\u597d<\/li>\n\n\n\n
      • \u2705 \u975e\u5e38\u9002\u5408\u7b97\u6cd5\u4f18\u5316<\/li>\n<\/ul>\n\n\n\n
        \n\n\n\n
        5\ufe0f\u20e3 \u6808\u4e0a\u7ed3\u6784\uff08\u91cd\u8981\u9650\u5236\uff09<\/h3>\n\n\n\n
        Span<T><\/code> \u662f\u4e00\u4e2a\uff1a<\/p>\n\n\n\n
        ref struct<\/code><\/pre>\n\n\n\n
        \u56e0\u6b64\u5b83\u6709\u4e00\u4e9b\u9650\u5236\uff1a<\/p>\n\n\n\n
          \n
        • \u274c \u4e0d\u80fd\u4f5c\u4e3a\u7c7b\u7684\u5b57\u6bb5<\/li>\n\n\n\n
        • \u274c \u4e0d\u80fd\u7528\u4e8e async \/ await<\/li>\n\n\n\n
        • \u274c \u4e0d\u80fd\u8de8\u65b9\u6cd5\u957f\u671f\u4fdd\u5b58<\/li>\n<\/ul>\n\n\n\n
          \ud83d\udc49 \u76ee\u7684\uff1a\u907f\u514d\u201c\u60ac\u7a7a\u5f15\u7528\u201d\uff0c\u4fdd\u8bc1\u5185\u5b58\u5b89\u5168<\/p>\n\n\n\n
          \n\n\n\n
          \u26a0\ufe0f \u56db\u3001\u4e3a\u4ec0\u4e48 Span \u6bd4\u6570\u7ec4\u5207\u7247\u66f4\u9ad8\u6548\uff1f<\/h2>\n\n\n\n
          \u274c \u6570\u7ec4\u5207\u7247\uff08\u4f1a\u590d\u5236\uff09<\/h3>\n\n\n\n
          var head = arr[..3];<\/code><\/pre>\n\n\n\n
          \u7b49\u4ef7\u4e8e\uff1a<\/p>\n\n\n\n
          var head = new int[] {1, 2, 3};<\/code><\/pre>\n\n\n\n
          \ud83d\udc49 \u521b\u5efa\u65b0\u6570\u7ec4 + \u62f7\u8d1d\u6570\u636e<\/p>\n\n\n\n
          \n\n\n\n
          \u2705 Span \u5207\u7247\uff08\u4e0d\u590d\u5236\uff09<\/h3>\n\n\n\n
          var head = arr.AsSpan()[..3];<\/code><\/pre>\n\n\n\n
          \ud83d\udc49 \u53ea\u662f\u6539\u53d8\u201c\u89c6\u56fe\u8303\u56f4\u201d<\/p>\n\n\n\n
          \n\n\n\n
          \ud83d\udcca \u4e94\u3001\u5bf9\u6bd4\u603b\u7ed3<\/h2>\n\n\n\n
          \u7c7b\u578b<\/th>\u662f\u5426\u590d\u5236<\/th>\u662f\u5426\u5206\u914d\u5185\u5b58<\/th>\u6027\u80fd<\/th><\/tr>
          int[]<\/code><\/td>\u274c<\/td>\u274c<\/td>\u4e00\u822c<\/td><\/tr>
          arr[..]<\/code><\/td>\u2705<\/td>\u2705<\/td>\u8f83\u6162<\/td><\/tr>
          Span<T><\/code><\/td>\u274c<\/td>\u274c<\/td>\ud83d\ude80 \u6781\u5feb<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
          \n\n\n\n
          \ud83d\ude80 \u516d\u3001\u5e38\u89c1\u4f7f\u7528\u65b9\u5f0f<\/h2>\n\n\n\n
          \u2714\ufe0f \u4ece\u6570\u7ec4\u521b\u5efa<\/h3>\n\n\n\n
          Span<int> s = arr;<\/code><\/pre>\n\n\n\n
          \n\n\n\n
          \u2714\ufe0f \u5207\u7247\u64cd\u4f5c<\/h3>\n\n\n\n
          var sub = s[2..5];<\/code><\/pre>\n\n\n\n
          \n\n\n\n
          \u2714\ufe0f \u904d\u5386<\/h3>\n\n\n\n
          foreach (var x in s)\n{\n    Console.WriteLine(x);\n}<\/code><\/pre>\n\n\n\n
          \n\n\n\n
          \u2714\ufe0f \u9ad8\u6027\u80fd\u66ff\u4ee3\u5199\u6cd5<\/h3>\n\n\n\n
          \u274c \u666e\u901a\u5199\u6cd5\uff1a<\/p>\n\n\n\n
          var temp = arr[..10];<\/code><\/pre>\n\n\n\n
          \u2705 \u63a8\u8350\u5199\u6cd5\uff1a<\/p>\n\n\n\n
          var temp = arr.AsSpan()[..10];<\/code><\/pre>\n\n\n\n
          \n\n\n\n
          \ud83d\udd25 \u4e03\u3001\u9002\u7528\u573a\u666f<\/h2>\n\n\n\n
          Span \u975e\u5e38\u9002\u5408\u4ee5\u4e0b\u573a\u666f\uff1a<\/p>\n\n\n\n
          \u2714\ufe0f \u7b97\u6cd5\u4e0e\u6570\u636e\u7ed3\u6784<\/h3>\n\n\n\n
            \n
          • \u52a8\u6001\u89c4\u5212\uff08DP\uff09<\/li>\n\n\n\n
          • \u6ed1\u52a8\u7a97\u53e3<\/li>\n\n\n\n
          • \u524d\u7f00\u548c<\/li>\n<\/ul>\n\n\n\n
            \u2714\ufe0f \u9ad8\u9891\u5faa\u73af<\/h3>\n\n\n\n
              \n
            • \u907f\u514d GC<\/li>\n\n\n\n
            • \u63d0\u5347\u7f13\u5b58\u547d\u4e2d\u7387<\/li>\n<\/ul>\n\n\n\n
              \u2714\ufe0f \u5b57\u7b26\u4e32\/\u6570\u7ec4\u5904\u7406<\/h3>\n\n\n\n
                \n
              • \u5b50\u4e32\u64cd\u4f5c<\/li>\n\n\n\n
              • \u6570\u636e\u89e3\u6790<\/li>\n<\/ul>\n\n\n\n
                \n\n\n\n
                \ud83e\udde0 \u516b\u3001Span vs Memory<\/h2>\n\n\n\n
                \u7c7b\u578b<\/td>\u662f\u5426\u5728\u6808<\/td>\u662f\u5426\u652f\u6301 async<\/td><\/tr>
                Span<T><\/code><\/td>\u2705<\/td>\u274c<\/td><\/tr>
                Memory<T><\/code><\/td>\u274c<\/td>\u2705<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
                \ud83d\udc49 \u7b80\u5355\u8bb0\uff1a<\/p>\n\n\n\n
                  \n
                • \u540c\u6b65\u9ad8\u6027\u80fd \u2192 Span<\/strong><\/li>\n\n\n\n
                • \u5f02\u6b65\u573a\u666f \u2192 Memory<\/strong><\/li>\n<\/ul>\n\n\n\n
                  \n\n\n\n
                  \ud83e\udde0 \u4e5d\u3001\u5e95\u5c42\u7406\u89e3\uff08\u8fdb\u9636\uff09<\/h2>\n\n\n\n
                  Span<T><\/code> \u672c\u8d28\u4e0a\u7c7b\u4f3c\u4e8e C\/C++ \u7684\uff1a<\/p>\n\n\n\n
                  T* pointer + length<\/code><\/pre>\n\n\n\n
                  \u4f46\u76f8\u6bd4\u6307\u9488\uff1a<\/p>\n\n\n\n
                    \n
                  • \u2705 \u6709\u8fb9\u754c\u68c0\u67e5<\/li>\n\n\n\n
                  • \u2705 \u7c7b\u578b\u5b89\u5168<\/li>\n\n\n\n
                  • \u2705 \u4e0d\u4f1a\u60ac\u7a7a\u5f15\u7528<\/li>\n<\/ul>\n\n\n\n
                    \ud83d\udc49 \u53ef\u4ee5\u7406\u89e3\u4e3a\uff1a\u201c\u5b89\u5168\u7248\u6307\u9488\u201d<\/strong><\/p>\n\n\n\n
                    \n\n\n\n
                    \ud83d\udccc \u5341\u3001\u603b\u7ed3<\/h2>\n\n\n\n
                    \n
                    Span<T> \u662f C# \u4e2d\u7528\u4e8e\u9ad8\u6027\u80fd\u7f16\u7a0b\u7684\u6838\u5fc3\u5de5\u5177\u4e4b\u4e00\uff0c\u901a\u8fc7\u201c\u96f6\u62f7\u8d1d\u89c6\u56fe\u201d\u5b9e\u73b0\u9ad8\u6548\u5185\u5b58\u64cd\u4f5c\u3002<\/strong><\/p>\n<\/blockquote>\n\n\n\n
                    \u8bb0\u4f4f\u8fd9\u4e09\u70b9\u5c31\u591f\u4e86\uff1a<\/p>\n\n\n\n
                      \n
                    1. Span<\/code> \u4e0d\u5b58\u6570\u636e\uff0c\u53ea\u662f\u89c6\u56fe<\/li>\n\n\n\n
                    2. \u5207\u7247\u4e0d\u4f1a\u590d\u5236\uff08\u96f6\u5f00\u9500\uff09<\/li>\n\n\n\n
                    3. \u9002\u7528\u4e8e\u6027\u80fd\u654f\u611f\u4ee3\u7801<\/li>\n<\/ol>\n\n\n\n
                      <\/p>\n","protected":false},"excerpt":{"rendered":"
                      \u5728\u73b0\u4ee3 C# \u5f00\u53d1\u4e2d\uff0c\u6027\u80fd\u4f18\u5316\u8d8a\u6765\u8d8a\u91cd\u8981\uff0c\u5c24\u5176\u662f\u5728\u5904\u7406\u5927\u91cf\u6570\u636e\u3001\u7b97\u6cd5\u4f18\u5316\uff08\u5982 DP\uff09\u3001\u6216\u9ad8\u9891\u8c03\u7528\u573a\u666f\u4e0b\u3002Span<T> …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"emotion":"","emotion_color":"","title_style":"","license":"","footnotes":""},"categories":[13],"tags":[8],"class_list":["post-53","post","type-post","status-publish","format-standard","hentry","category-13","tag-c"],"_links":{"self":[{"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/posts\/53","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/comments?post=53"}],"version-history":[{"count":1,"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/posts\/53\/revisions"}],"predecessor-version":[{"id":54,"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/posts\/53\/revisions\/54"}],"wp:attachment":[{"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/media?parent=53"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/categories?post=53"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.bandifee.com\/index.php\/wp-json\/wp\/v2\/tags?post=53"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}