{"id":691,"date":"2021-09-19T19:52:24","date_gmt":"2021-09-19T11:52:24","guid":{"rendered":"https:\/\/swordofmorning.com\/?p=691"},"modified":"2025-10-09T13:55:51","modified_gmt":"2025-10-09T05:55:51","slug":"function-bind-introduction","status":"publish","type":"post","link":"https:\/\/swordofmorning.com\/index.php\/2021\/09\/19\/function-bind-introduction\/","title":{"rendered":"std::function\u548cstd::bind\u7b80\u4ecb"},"content":{"rendered":"<p><div class=\"has-toc have-toc\"><\/div><\/p>\n<h2>\u4e00\u3001\u53ef\u8c03\u7528\u5bf9\u8c61<\/h2>\n<p>&emsp;&emsp;\u53ef\u8c03\u7528\u5bf9\u8c61\u6709\u5982\u4e0b\u51e0\u79cd\u5b9a\u4e49\uff1a<\/p>\n<ul>\n<li>\u662f\u4e00\u4e2a\u51fd\u6570\u6307\u9488\uff0c\u53c2\u8003 C++ \u51fd\u6570\u6307\u9488\u548c\u51fd\u6570\u7c7b\u578b\uff1b<\/li>\n<li>\u662f\u4e00\u4e2a\u5177\u6709operator()\u6210\u5458\u51fd\u6570\u7684\u7c7b\u7684\u5bf9\u8c61\uff1b<\/li>\n<li>\u53ef\u88ab\u8f6c\u6362\u6210\u51fd\u6570\u6307\u9488\u7684\u7c7b\u5bf9\u8c61\uff1b<\/li>\n<li>\u4e00\u4e2a\u7c7b\u6210\u5458\u51fd\u6570\u6307\u9488\uff1b<\/li>\n<\/ul>\n<p>&emsp;&emsp;C++\u4e2d\u53ef\u8c03\u7528\u5bf9\u8c61\u7684\u867d\u7136\u90fd\u6709\u4e00\u4e2a\u6bd4\u8f83\u7edf\u4e00\u7684\u64cd\u4f5c\u5f62\u5f0f\uff0c\u4f46\u662f\u5b9a\u4e49\u65b9\u6cd5\u4e94\u82b1\u516b\u95e8\uff0c\u8fd9\u6837\u5c31\u5bfc\u81f4\u4f7f\u7528\u7edf\u4e00\u7684\u65b9\u5f0f\u4fdd\u5b58\u53ef\u8c03\u7528\u5bf9\u8c61\u6216\u8005\u4f20\u9012\u53ef\u8c03\u7528\u5bf9\u8c61\u65f6\uff0c\u4f1a\u5341\u5206\u7e41\u7410\u3002C++11\u4e2d\u63d0\u4f9b\u4e86std::function\u548cstd::bind\u7edf\u4e00\u4e86\u53ef\u8c03\u7528\u5bf9\u8c61\u7684\u5404\u79cd\u64cd\u4f5c\u3002<\/p>\n<pre><code class=\"language-cpp\">\/\/ \u666e\u901a\u51fd\u6570\nint add(int a, int b)\n{\n    return a + b;\n}\n\n\/\/ lambda\u8868\u8fbe\u5f0f\nauto mod = [](int a, int b)\n{\n    return a + b;\n};\n\n\/\/ \u51fd\u6570\u5bf9\u8c61\u7c7b\nstruct minus\n{\n    int operator()(int a, int b)\n    {\n        return a - b;\n    }\n};<\/code><\/pre>\n<p>&emsp;&emsp;\u4e0a\u8ff0\u4e09\u79cd\u53ef\u8c03\u7528\u5bf9\u8c61\u867d\u7136\u7c7b\u578b\u4e0d\u540c\uff0c\u4f46\u662f\u5171\u4eab\u4e86\u4e00\u79cd\u8c03\u7528\u5f62\u5f0f\uff1a<\/p>\n<pre><code class=\"language-cpp\">int(int ,int)<\/code><\/pre>\n<p>&emsp;&emsp;\u901a\u8fc7std::function\u53ef\u4ee5\u5c06\u4e0a\u8ff0\u7c7b\u578b\u4fdd\u5b58\u4e0b\u6765\uff1a<\/p>\n<pre><code class=\"language-cpp\">std::function&lt;int(int, int)&gt; addFunc = add;\nstd::function&lt;int(int, int)&gt; modFunc = mod;\nstd::function&lt;int(int, int)&gt; minusFunc = minus();<\/code><\/pre>\n<h2>\u4e8c std::function<\/h2>\n<ul>\n<li>std::function \u662f\u4e00\u4e2a\u53ef\u8c03\u7528\u5bf9\u8c61\u5305\u88c5\u5668\uff0c\u662f\u4e00\u4e2a\u7c7b\u6a21\u677f\uff0c\u53ef\u4ee5\u5bb9\u7eb3\u9664\u4e86\u7c7b\u6210\u5458\u51fd\u6570\u6307\u9488\u4e4b\u5916\u7684\u6240\u6709\u53ef\u8c03\u7528\u5bf9\u8c61\uff0c\u5b83\u53ef\u4ee5\u7528\u7edf\u4e00\u7684\u65b9\u5f0f\u5904\u7406\u51fd\u6570\u3001\u51fd\u6570\u5bf9\u8c61\u3001\u51fd\u6570\u6307\u9488\uff0c\u5e76\u5141\u8bb8\u4fdd\u5b58\u548c\u5ef6\u8fdf\u5b83\u4eec\u7684\u6267\u884c\u3002<\/li>\n<li>\u5b9a\u4e49\u683c\u5f0f\uff1astd::function&lt;\u51fd\u6570\u7c7b\u578b&gt;\u3002<\/li>\n<li>std::function\u53ef\u4ee5\u53d6\u4ee3\u51fd\u6570\u6307\u9488\u7684\u4f5c\u7528\uff0c\u56e0\u4e3a\u5b83\u53ef\u4ee5\u5ef6\u8fdf\u51fd\u6570\u7684\u6267\u884c\uff0c\u7279\u522b\u9002\u5408\u4f5c\u4e3a\u56de\u8c03\u51fd\u6570\u4f7f\u7528\u3002\u5b83\u6bd4\u666e\u901a\u51fd\u6570\u6307\u9488\u66f4\u52a0\u7684\u7075\u6d3b\u548c\u4fbf\u5229\u3002<\/li>\n<\/ul>\n<h2>\u4e09 std::bind<\/h2>\n<p>&emsp;&emsp;\u5b83\u7684\u4e3b\u8981\u529f\u80fd\u5c31\u662f\u4f5c\u4e3a<strong>\u51fd\u6570\u9002\u914d\u5668<\/strong>\uff0c\u5b83\u63a5\u53d7\u4e00\u4e2a\u53ef\u8c03\u7528\u5bf9\u8c61\uff0c\u5e76\u751f\u6210\u4e00\u4e2a\u65b0\u7684\u53ef\u8c03\u7528\u5bf9\u8c61\u3002\u540c\u65f6\uff0cstd::bind\u53ef\u4ee5\u7ed1\u5b9a\u53c2\u6570\uff08\u7c7b\u4f3cstd::thread\uff09\uff0c\u5e76\u4e14\u53ef\u4ee5\u4f7f\u7528\u5360\u4f4d\u7b26\u4ee3\u66ff\uff0c\u5176\u505a\u6cd5\u5f88\u7c7b\u4f3c\u4e8e\u6570\u636e\u67e5\u8be2\u65f6\u6240\u4f7f\u7528\u7684\u4f7f\u7528\u5360\u4f4d\u7b26\u5148\u89e3\u6790\u3002std::bind\u4e3b\u8981\u6709\u4ee5\u4e0b\u4e24\u4e2a\u4f5c\u7528\uff1a<\/p>\n<ul>\n<li>\u5c06\u53ef\u8c03\u7528\u5bf9\u8c61\u548c\u5176\u53c2\u6570\u7ed1\u5b9a\u6210\u4e00\u4e2a\u4eff\u51fd\u6570\uff1b<\/li>\n<li>\u53ea\u7ed1\u5b9a\u90e8\u5206\u53c2\u6570\uff0c\u51cf\u5c11\u53ef\u8c03\u7528\u5bf9\u8c61\u4f20\u5165\u7684\u53c2\u6570\u3002<\/li>\n<\/ul>\n<h3>3.1 \u7ed1\u5b9a\u666e\u901a\u51fd\u6570<\/h3>\n<pre><code class=\"language-cpp\">#include &lt;iostream&gt;\n#include &lt;functional&gt;\n\nint add(int a, int b)\n{\n    return a + b;\n}\n\nint main()\n{\n    \/* ===== \u7ed1\u5b9a\u9ed8\u8ba4\u53c2\u6570 ===== *\/\n\n    auto defaultAdd = std::bind(add, 5, 6);\n\n    std::cout &lt;&lt; defaultAdd() &lt;&lt; std::endl;\n\n    \/* ===== \u4f7f\u7528\u4e00\u4e2a\u5360\u4f4d\u7b26 ===== *\/\n\n    auto placeholderAdd = std::bind(add, std::placeholders::_1, 6);\n\n    std::cout &lt;&lt; placeholderAdd(5) &lt;&lt; std::endl;\n\n    return 0;\n}<\/code><\/pre>\n<p>&emsp;&emsp;\u4e0estd::thread\u76f8\u4f3c\uff0c\u7b2c\u4e00\u4e2a\u53c2\u6570\u662f\u51fd\u6570\u540d\uff0c\u666e\u901a\u51fd\u6570\u505a\u5b9e\u53c2\u65f6\u4f1a\u9690\u5f0f\u8f6c\u6362\u4e3a\u51fd\u6570\u6307\u9488\u3002\u56e0\u6b64\uff1a<\/p>\n<pre><code class=\"language-cpp\">auto defaultAdd = std::bind(add, 5, 6);\n\/\/ equal\nauto defaultAdd = std::bind(&amp;add, 5, 6);<\/code><\/pre>\n<h3>3.2 \u7ed1\u5b9a\u6210\u5458\u51fd\u6570<\/h3>\n<pre><code class=\"language-cpp\">#include &lt;iostream&gt;\n#include &lt;functional&gt;\n\nclass Cal\n{\npublic:\n    int add(const int&amp; a, const int&amp; b)\n    {\n        return a + b;\n    }\n};\n\nint main()\n{\n    Cal calculator;\n    auto callBind = std::bind(&amp;Cal::add, &amp;calculator, std::placeholders::_1, std::placeholders::_2);\n\n    \/\/ auto callBind = std::bind(&amp;Cal::add, calculator, std::placeholders::_1, std::placeholders::_2);\n\n    \/\/ auto callBind = std::bind(&amp;Cal::add, Cal(), std::placeholders::_1, std::placeholders::_2);\n\n    std::cout &lt;&lt; callBind(5, 1) &lt;&lt; std::endl;\n\n    return 0;\n}<\/code><\/pre>\n<p>&emsp;&emsp;\u8fd9\u91cc\u9700\u8981\u6ce8\u610f\uff0c\u6ce8\u91ca\u90e8\u5206\u4e5f\u662f\u53ef\u884c\u7684\uff0c\u5bf9\u8c61\u4ee5<strong>\u62f7\u8d1d\uff08Copied\uff09<\/strong>\u7684\u65b9\u5f0f\u88ab\u4f20\u5165std::bind\u5bf9\u8c61\u3002\u4f46\u662f\uff0c\u5bf9\u4e8e\u4e0d\u53ef\u4ee5\u4ee5\u62f7\u8d1d\u65b9\u5f0f\u4f20\u5165\u7684\u5bf9\u8c61\uff08std::unique_ptr\u4e00\u7c7b\uff09\u9700\u8981\u989d\u5916\u6ce8\u610f\u3002<br \/>\n&emsp;&emsp;\u4e0b\u9762\u8bf4\u660e\u4e0a\u8ff0\u4ee3\u7801\u4e2d\u7684bind\u53c2\u6570\uff1a<\/p>\n<ol>\n<li>\u7b2c\u4e00\u53c2\u6570\u4e3a\u6307\u5411\u6210\u5458\u51fd\u6570\u7684\u6307\u9488\u3002\u5176\u53ef\u4ee5\u4f7f\u7528&amp;Fname\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528std::mem_fn(&amp;Fname)\u5bf9\u8c61\u3002<\/li>\n<li>\u7b2c\u4e8c\u53c2\u6570\u4e3a\u6210\u5458\u51fd\u6570\u6307\u9488\u6240\u5c5e\u7684\u5177\u4f53\u5bf9\u8c61\u3002<\/li>\n<\/ol>\n<h3>3.3 \u7ed1\u5b9a\u5f15\u7528\u53c2\u6570<\/h3>\n<pre><code class=\"language-cpp\">#include &lt;iostream&gt;\n#include &lt;functional&gt;\n\nint add(int a, int&amp; b)\n{\n    return a + b++;\n}\n\nint main()\n{\n    int param{ 5 };\n\n    auto addFunc = std::bind(&amp;add, 0, std::ref(param));\n\n    addFunc();\n\n    std::cout &lt;&lt; param &lt;&lt; std::endl;\n\n    return 0;\n}<\/code><\/pre>\n<p>&emsp;&emsp;\u5343\u8a00\u4e07\u8bed\u6c47\u6210\u4e00\u53e5\uff1a\u4f7f\u7528std::ref\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f20\u5165\u5bf9\u8c61\u3002<\/p>\n<h3>3.4 \u9644\u8a00<\/h3>\n<p>&emsp;&emsp;\u4e0d\u8981\u5c1d\u8bd5\u7528std::bind\u53bb\u7ed1\u5b9astd::unique_ptr\uff0c\u5176\u5b9e\u662f\u6211\u4e0d\u4f1a\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e00\u3001\u53ef\u8c03\u7528\u5bf9\u8c61 &emsp;&emsp;\u53ef\u8c03\u7528\u5bf9\u8c61\u6709\u5982\u4e0b\u51e0\u79cd\u5b9a\u4e49\uff1a \u662f\u4e00\u4e2a\u51fd\u6570\u6307\u9488\uff0c\u53c2\u8003 C++ \u51fd\u6570\u6307\u9488\u548c\u51fd\u6570\u7c7b\u578b\uff1b \u662f\u4e00\u4e2a\u5177\u6709 &#8230;<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[48],"tags":[14],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/posts\/691"}],"collection":[{"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/comments?post=691"}],"version-history":[{"count":7,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/posts\/691\/revisions"}],"predecessor-version":[{"id":701,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/posts\/691\/revisions\/701"}],"wp:attachment":[{"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/media?parent=691"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/categories?post=691"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/tags?post=691"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}