{"id":4034,"date":"2019-12-20T10:13:40","date_gmt":"2019-12-20T02:13:40","guid":{"rendered":"https:\/\/damogame.cn\/wordpress\/?p=4034"},"modified":"2019-12-20T10:13:40","modified_gmt":"2019-12-20T02:13:40","slug":"c11%e4%b8%ad%e7%9a%84stdbind","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/4034","title":{"rendered":"C++11\u4e2d\u7684std::bind"},"content":{"rendered":"<div class=\"clear\"><a href=\"https:\/\/www.cnblogs.com\/lzya\/p\/4912993.html\">\u539f\u6587\u5730\u5740<\/a><\/div>\n<div><\/div>\n<div class=\"postBody\">\n<div id=\"cnblogs_post_body\" class=\"blogpost-body \">\n<h4 id=\"\u770b\u770b\u8fd9\u6bb5\u4ee3\u7801\">\u770b\u770b\u8fd9\u6bb5\u4ee3\u7801<\/h4>\n<p>\u8fd9\u51e0\u5929\u5b66\u4e60Cocos2d-x\uff0c\u770b\u5230\u4e86\u4ee5\u4e0b\u7684\u4e00\u6bb5\u4ee3\u7801\uff1a<\/p>\n<pre><code class=\"language-cpp hljs\"><span class=\"hljs-comment\">\/\/ new callbacks based on C++11<\/span>\r\n<span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">define<\/span><\/span><\/span><span class=\"hljs-meta\"> CC_CALLBACK_0(__selector__,__target__, ...) std::bind(&amp;__selector__,__target__, ##__VA_ARGS__)<\/span><\/span>\r\n\r\n<span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">define<\/span><\/span><\/span><span class=\"hljs-meta\"> CC_CALLBACK_1(__selector__,__target__, ...) std::bind(&amp;__selector__,__target__, std::placeholders::_1, ##__VA_ARGS__)<\/span><\/span>\r\n\r\n<span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">define<\/span><\/span><\/span><span class=\"hljs-meta\"> CC_CALLBACK_2(__selector__,__target__, ...) std::bind(&amp;__selector__,__target__, std::placeholders::_1, std::placeholders::_2, ##__VA_ARGS__)<\/span><\/span>\r\n\r\n<span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">define<\/span><\/span><\/span><span class=\"hljs-meta\"> CC_CALLBACK_3(__selector__,__target__, ...) std::bind(&amp;__selector__,__target__, std::placeholders::_1, std::placeholders::_2, std::placeholders::_3, ##__VA_ARGS__)<\/span><\/span>\r\n<\/code><\/pre>\n<p>\u90fd\u662f\u5b9a\u4e49\u7684\u4e00\u4e9b\u5b8f\uff0c\u5982\u679c\u4f60\u770b\u4e86\u4e0a\u9762\u7684\u8fd9\u6bb5\u4ee3\u7801\uff0c\u89c9\u7684\u5f88\u7b80\u5355\uff0c\u90a3\u4e48\u8fd9\u7bc7\u6587\u7ae0\u4f60\u5b8c\u5168\u53ef\u4ee5pass\u4e86\uff1b\u5982\u679c\u4f60\u5bf9\u4e0a\u9762\u5b9a\u4e49\u7684\u8fd9\u4e9b\u5b8f\uff0c\u5b8c\u5168\u4e0d\u77e5\u9053\u662f\u4ec0\u4e48\u610f\u601d\uff0c\u90a3\u4e48\uff0c\u8fd9\u7bc7\u6587\u7ae0\u5c31\u5c5e\u4e8e\u4f60\uff0c\u5b8c\u5168\u5c5e\u4e8e\u4f60\u7684\u83dc\u3002<\/p>\n<p>\u901a\u8fc7\u8fd9\u7bc7\u6587\u7ae0\uff0c\u6211\u5c06\u5e26\u4f60\u8fdb\u5165C++11\u4e2dstd::bind\u7684\u4e16\u754c\uff0c\u8ba9\u6211\u4eec\u8d77\u822a\u5427\u3002<\/p>\n<h4 id=\"\u5148\u6765\u770b\u770bstdbind1st\u548cstdbind2nd\">\u5148\u6765\u770b\u770bstd::bind1st\u548cstd::bind2nd<\/h4>\n<p>bind\u662f\u8fd9\u6837\u4e00\u79cd\u673a\u5236\uff0c\u5b83\u53ef\u4ee5\u9884\u5148\u628a\u6307\u5b9a\u53ef\u8c03\u7528\u5b9e\u4f53\u7684\u67d0\u4e9b\u53c2\u6570\u7ed1\u5b9a\u5230\u5df2\u6709\u7684\u53d8\u91cf\uff0c\u4ea7\u751f\u4e00\u4e2a\u65b0\u7684\u53ef\u8c03 \u7528\u5b9e\u4f53\uff0c\u8fd9\u79cd\u673a\u5236\u5728\u56de\u8c03\u51fd\u6570\u7684\u4f7f\u7528\u8fc7\u7a0b\u4e2d\u4e5f\u9887\u4e3a\u6709\u7528\u3002C++98\u4e2d\uff0c\u6709\u4e24\u4e2a\u51fd\u6570bind1st\u548cbind2nd\uff0c\u5b83\u4eec\u5206\u522b\u53ef\u4ee5\u7528\u6765\u7ed1\u5b9afunctor\u7684\u7b2c \u4e00\u4e2a\u548c\u7b2c\u4e8c\u4e2a\u53c2\u6570\uff0c\u5b83\u4eec\u90fd\u662f\u53ea\u53ef\u4ee5\u7ed1\u5b9a\u4e00\u4e2a\u53c2\u6570\u3002\u5404\u79cd\u9650\u5236\uff0c\u4f7f\u5f97bind1st\u548cbind2nd\u7684\u53ef\u7528\u6027\u5927\u5927\u964d\u4f4e\u3002<\/p>\n<p>\u5982\u679c\u901a\u8fc7\u4e0a\u9762\u7684\u5185\u5bb9\uff0c\u4f60\u8fd8\u6ca1\u6709\u660e\u767dstd::bind1st\u548cstd::bind2nd\u5230\u5e95\u662f\u4f55\u65b9\u5723\u795e\u5230\u5e95\u662f\u4ec0\u4e48\u4e1c\u897f\uff0c\u90a3\u5c31\u770b\u8fd9\u6bb5\u4ee3\u7801\u793a\u4f8b\uff1a<\/p>\n<pre><code class=\"language-cpp hljs\"><span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">include<\/span><\/span><\/span><span class=\"hljs-meta\"> <span class=\"hljs-meta-string\">&lt;iostream&gt;<\/span><\/span><\/span>\r\n<span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">include<\/span><\/span><\/span><span class=\"hljs-meta\"> <span class=\"hljs-meta-string\">&lt;functional&gt;<\/span><\/span><\/span>\r\n<span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">include<\/span><\/span><\/span><span class=\"hljs-meta\"> <span class=\"hljs-meta-string\">&lt;algorithm&gt;<\/span><\/span><\/span>\r\n<span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">include<\/span><\/span><\/span><span class=\"hljs-meta\"> <span class=\"hljs-meta-string\">&lt;vector&gt;<\/span><\/span><\/span>\r\n<span class=\"hljs-keyword\">using<\/span> <span class=\"hljs-keyword\">namespace<\/span> <span class=\"hljs-built_in\">std<\/span>;\r\n\r\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">int<\/span> <span class=\"hljs-title\">main<\/span><span class=\"hljs-params\">()<\/span>\r\n<\/span>{\r\n    <span class=\"hljs-stl_container\"><span class=\"hljs-built_in\">vector<\/span>&lt;<span class=\"hljs-keyword\">int<\/span>&gt;<\/span> coll;\r\n    <span class=\"hljs-keyword\">for<\/span> (<span class=\"hljs-keyword\">int<\/span> i = <span class=\"hljs-number\">1<\/span>; i &lt;= <span class=\"hljs-number\">10<\/span>; ++i)\r\n    {\r\n        coll.push_back(i);\r\n    }\r\n\r\n    <span class=\"hljs-comment\">\/\/ \u67e5\u627e\u5143\u7d20\u503c\u5927\u4e8e10\u7684\u5143\u7d20\u7684\u4e2a\u6570<\/span>\r\n    <span class=\"hljs-comment\">\/\/ \u4e5f\u5c31\u662f\u4f7f\u5f9710 &lt; elem\u6210\u7acb\u7684\u5143\u7d20\u4e2a\u6570 <\/span>\r\n    <span class=\"hljs-keyword\">int<\/span> res = count_if(coll.begin(), coll.end(), bind1st(less&lt;<span class=\"hljs-keyword\">int<\/span>&gt;(), <span class=\"hljs-number\">10<\/span>));\r\n    <span class=\"hljs-built_in\">cout<\/span> &lt;&lt; res &lt;&lt; <span class=\"hljs-built_in\">endl<\/span>;\r\n\r\n    <span class=\"hljs-comment\">\/\/ \u67e5\u627e\u5143\u7d20\u503c\u5c0f\u4e8e10\u7684\u5143\u7d20\u7684\u4e2a\u6570<\/span>\r\n    <span class=\"hljs-comment\">\/\/ \u4e5f\u5c31\u662f\u4f7f\u5f97elem &lt; 10\u6210\u7acb\u7684\u5143\u7d20\u4e2a\u6570 <\/span>\r\n    res = count_if(coll.begin(), coll.end(), bind2nd(less&lt;<span class=\"hljs-keyword\">int<\/span>&gt;(), <span class=\"hljs-number\">10<\/span>));\r\n    <span class=\"hljs-built_in\">cout<\/span> &lt;&lt; res &lt;&lt; <span class=\"hljs-built_in\">endl<\/span>;\r\n\r\n    <span class=\"hljs-keyword\">return<\/span> <span class=\"hljs-number\">0<\/span>;\r\n}\r\n<\/code><\/pre>\n<p>\u901a\u8fc7\u4e0a\u9762\u7684\u4ee3\u7801\u660e\u767d\u4e86std::bind1st\u548cstd::bind2nd\u4e86\u4e48\uff1f\u8fd8\u6ca1\u6709\u660e\u767d\uff1f\u597d\u5427\uff0c\u6211\u63a5\u7740\u5f80\u7ec6\u4e86\u8bb2\u3002<\/p>\n<p>\u5bf9\u4e8e\u4e0a\u9762\u7684\u4ee3\u7801\uff0c<code>less&lt;int&gt;()<\/code>\u5176\u5b9e\u662f\u4e00\u4e2a\u4eff\u51fd\u6570\uff0c\u5982\u679c\u6ca1\u6709std::bind1st\u548cstd::bind2nd\uff0c\u90a3\u4e48\u6211\u4eec\u53ef\u4ee5\u8fd9\u6837\u4f7f\u7528<code>less&lt;int&gt;()<\/code>\uff0c\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n<pre><code class=\"language-cpp hljs\">less&lt;<span class=\"hljs-keyword\">int<\/span>&gt; functor = less&lt;<span class=\"hljs-keyword\">int<\/span>&gt;();\r\n<span class=\"hljs-keyword\">bool<\/span> bRet = functor(<span class=\"hljs-number\">10<\/span>, <span class=\"hljs-number\">20<\/span>); <span class=\"hljs-comment\">\/\/ \u8fd4\u56detrue<\/span>\r\n<\/code><\/pre>\n<p>\u770b\u5230\u4e86\u4e48\uff1f<code>less&lt;int&gt;()<\/code>\u8fd9\u4e2a\u4eff\u51fd\u6570\u5bf9\u8c61\u662f\u9700\u8981\u4e24\u4e2a\u53c2\u6570\u7684\uff0c\u6bd4\u598210&lt;20\u8fdb\u884c\u6bd4\u8f83\uff0c\u90a3\u4e4810\u53eb\u505aleft\u53c2\u6570\uff0c20\u53eb\u505aright\u53c2\u6570\u3002<\/p>\n<ul>\n<li>\u5f53\u4f7f\u7528<code>std::bind1st<\/code>\u7684\u65f6\u5019\uff0c\u5c31\u8868\u793a\u7ed1\u5b9a\u4e86left\u53c2\u6570\uff0c\u4e5f\u5c31\u662fleft\u53c2\u6570\u4e0d\u53d8\u4e86\uff0c\u800cright\u53c2\u6570\u5c31\u662f\u5bf9\u5e94\u5bb9\u5668\u4e2d\u7684element\uff1b<\/li>\n<li>\u5f53\u4f7f\u7528<code>std::bind2nd<\/code>\u7684\u65f6\u5019\uff0c\u5c31\u8868\u793a\u7ed1\u5b9a\u4e86right\u53c2\u6570\uff0c\u4e5f\u5c31\u662fright\u53c2\u6570\u4e0d\u53d8\u4e86\uff0c\u800cleft\u53c2\u6570\u5c31\u662f\u5bf9\u5e94\u5bb9\u5668\u4e2d\u7684element\u3002<\/li>\n<\/ul>\n<p>\u8fd9\u4e0b\u5e94\u8be5\u8bb2\u660e\u767d\u4e86\u3002<\/p>\n<h4 id=\"\u518d\u6765\u770b\u770bstdbind\">\u518d\u6765\u770b\u770bstd::bind<\/h4>\n<p>C++11\u4e2d\u63d0\u4f9b\u4e86<code>std::bind<\/code>\u3002bind()\u51fd\u6570\u7684\u610f\u4e49\u5c31\u50cf\u5b83\u7684\u51fd\u6570\u540d\u4e00\u6837\uff0c\u662f\u7528\u6765\u7ed1\u5b9a\u51fd\u6570\u8c03\u7528\u7684\u67d0\u4e9b\u53c2\u6570\u7684\u3002<\/p>\n<p>bind\u7684\u601d\u60f3\u5b9e\u9645\u4e0a\u662f\u4e00\u79cd\u5ef6\u8fdf\u8ba1\u7b97\u7684\u601d\u60f3\uff0c\u5c06\u53ef\u8c03\u7528\u5bf9\u8c61\u4fdd\u5b58\u8d77\u6765\uff0c\u7136\u540e\u5728\u9700\u8981\u7684\u65f6\u5019\u518d\u8c03\u7528\u3002\u800c\u4e14\u8fd9\u79cd\u7ed1\u5b9a\u662f\u975e\u5e38\u7075\u6d3b\u7684\uff0c\u4e0d\u8bba\u662f\u666e\u901a\u51fd\u6570\u3001\u51fd\u6570\u5bf9\u8c61\u3001\u8fd8\u662f\u6210\u5458\u51fd\u6570\u90fd\u53ef\u4ee5\u7ed1\u5b9a\uff0c\u800c\u4e14\u5176\u53c2\u6570\u53ef\u4ee5\u652f\u6301\u5360\u4f4d\u7b26\uff0c\u6bd4\u5982\u4f60\u53ef\u4ee5\u8fd9\u6837\u7ed1\u5b9a\u4e00\u4e2a\u4e8c\u5143\u51fd\u6570<code>auto f = bind(&amp;func, _1, _2);<\/code>\uff0c\u8c03\u7528\u7684\u65f6\u5019\u901a\u8fc7f(1,2)\u5b9e\u73b0\u8c03\u7528\u3002<\/p>\n<p>\u7b80\u5355\u7684\u8ba4\u4e3a\u5c31\u662f<code>std::bind<\/code>\u5c31\u662f<code>std::bind1st<\/code>\u548c<code>std::bind2nd<\/code>\u7684\u52a0\u5f3a\u7248\u3002<\/p>\n<h4 id=\"\u600e\u4e48\u4f7f\u7528stdbind\">\u600e\u4e48\u4f7f\u7528std::bind<\/h4>\n<p>\u4e00\u4e2a\u77e5\u8bc6\u70b9\u5389\u4e0d\u5389\u5bb3\uff0c\u5f52\u6839\u5230\u5e95\u8fd8\u662f\u8981\u7ecf\u8fc7\u5b9e\u8df5\u7684\u8003\u9a8c\uff0c\u4e0b\u9762\u5c31\u6765\u770b\u770b<code>std::bind<\/code>\u5230\u5e95\u600e\u4e48\u7528\u3002<\/p>\n<p>\u5148\u770b\u770b\u300a<a href=\"http:\/\/www.jellythink.com\/archives\/771\" target=\"_blank\" rel=\"noopener noreferrer\">C++11\u4e2d\u7684std::function<\/a>\u300b\u4e2d\u90a3\u6bb5\u4ee3\u7801\uff0c<code>std::function<\/code>\u53ef\u4ee5\u7ed1\u5b9a\u5168\u5c40\u51fd\u6570\uff0c\u9759\u6001\u51fd\u6570\uff0c\u4f46\u662f\u7ed1\u5b9a\u7c7b\u7684\u6210\u5458\u51fd\u6570\u65f6\uff0c\u5fc5\u987b\u8981\u501f\u52a9<code>std::bind<\/code>\u7684\u5e2e\u5fd9\u3002\u4f46\u662f\u8bdd\u53c8\u8bf4\u56de\u6765\uff0c\u4e0d\u501f\u52a9<code>std::bind<\/code>\u4e5f\u662f\u53ef\u4ee5\u5b8c\u6210\u7684\uff0c\u53ea\u9700\u8981\u4f20\u4e00\u4e2a*this\u53d8\u91cf\u8fdb\u53bb\u5c31\u597d\u4e86\uff0c\u6bd4\u5982\uff1a<\/p>\n<pre><code class=\"language-cpp hljs\"><span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">include<\/span><\/span><\/span><span class=\"hljs-meta\"> <span class=\"hljs-meta-string\">&lt;iostream&gt;<\/span><\/span><\/span>\r\n<span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">include<\/span><\/span><\/span><span class=\"hljs-meta\"> <span class=\"hljs-meta-string\">&lt;functional&gt;<\/span><\/span><\/span>\r\n<span class=\"hljs-keyword\">using<\/span> <span class=\"hljs-keyword\">namespace<\/span> <span class=\"hljs-built_in\">std<\/span>;\r\n\r\n<span class=\"hljs-keyword\"><span class=\"hljs-class\">class<\/span><\/span><span class=\"hljs-class\"> <span class=\"hljs-title\">View<\/span>\r\n{<\/span>\r\n<span class=\"hljs-keyword\">public<\/span>:\r\n    <span class=\"hljs-function\"><span class=\"hljs-keyword\">void<\/span> <span class=\"hljs-title\">onClick<\/span><span class=\"hljs-params\">(<span class=\"hljs-keyword\">int<\/span> x, <span class=\"hljs-keyword\">int<\/span> y)<\/span>\r\n    <\/span>{\r\n        <span class=\"hljs-built_in\">cout<\/span> &lt;&lt; <span class=\"hljs-string\">\"X : \"<\/span> &lt;&lt; x &lt;&lt; <span class=\"hljs-string\">\", Y : \"<\/span> &lt;&lt; y &lt;&lt; <span class=\"hljs-built_in\">endl<\/span>;\r\n    }\r\n};\r\n\r\n<span class=\"hljs-comment\">\/\/ \u5b9a\u4e49function\u7c7b\u578b, \u4e09\u4e2a\u53c2\u6570<\/span>\r\nfunction&lt;<span class=\"hljs-keyword\">void<\/span>(View, <span class=\"hljs-keyword\">int<\/span>, <span class=\"hljs-keyword\">int<\/span>)&gt; clickCallback;\r\n\r\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">int<\/span> <span class=\"hljs-title\">main<\/span><span class=\"hljs-params\">(<span class=\"hljs-keyword\">int<\/span> argc, <span class=\"hljs-keyword\">const<\/span> <span class=\"hljs-keyword\">char<\/span> * argv[])<\/span>\r\n<\/span>{\r\n    View button;\r\n\r\n    <span class=\"hljs-comment\">\/\/ \u6307\u5411\u6210\u5458\u51fd\u6570<\/span>\r\n    clickCallback = &amp;View::onClick;\r\n\r\n    <span class=\"hljs-comment\">\/\/ \u8fdb\u884c\u8c03\u7528<\/span>\r\n    clickCallback(button, <span class=\"hljs-number\">10<\/span>, <span class=\"hljs-number\">123<\/span>);\r\n    <span class=\"hljs-keyword\">return<\/span> <span class=\"hljs-number\">0<\/span>;\r\n}\r\n<\/code><\/pre>\n<p>\u518d\u6765\u4e00\u6bb5\u793a\u4f8b\u8c08\u8c08\u600e\u4e48\u4f7f\u7528std::bind\u4ee3\u7801\uff1a<\/p>\n<pre><code class=\"language-cpp hljs\"><span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">include<\/span><\/span><\/span><span class=\"hljs-meta\"> <span class=\"hljs-meta-string\">&lt;iostream&gt;<\/span><\/span><\/span>\r\n<span class=\"hljs-preprocessor\"><span class=\"hljs-meta\">#<\/span><span class=\"hljs-keyword\"><span class=\"hljs-meta\"><span class=\"hljs-meta-keyword\">include<\/span><\/span><\/span><span class=\"hljs-meta\"> <span class=\"hljs-meta-string\">&lt;functional&gt;<\/span><\/span><\/span>\r\n<span class=\"hljs-keyword\">using<\/span> <span class=\"hljs-keyword\">namespace<\/span> <span class=\"hljs-built_in\">std<\/span>;\r\n\r\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">int<\/span> <span class=\"hljs-title\">TestFunc<\/span><span class=\"hljs-params\">(<span class=\"hljs-keyword\">int<\/span> a, <span class=\"hljs-keyword\">char<\/span> c, <span class=\"hljs-keyword\">float<\/span> f)<\/span>\r\n<\/span>{\r\n    <span class=\"hljs-built_in\">cout<\/span> &lt;&lt; a &lt;&lt; <span class=\"hljs-built_in\">endl<\/span>;\r\n    <span class=\"hljs-built_in\">cout<\/span> &lt;&lt; c &lt;&lt; <span class=\"hljs-built_in\">endl<\/span>;\r\n    <span class=\"hljs-built_in\">cout<\/span> &lt;&lt; f &lt;&lt; <span class=\"hljs-built_in\">endl<\/span>;\r\n\r\n    <span class=\"hljs-keyword\">return<\/span> a;\r\n}\r\n\r\n<span class=\"hljs-function\"><span class=\"hljs-keyword\">int<\/span> <span class=\"hljs-title\">main<\/span><span class=\"hljs-params\">()<\/span>\r\n<\/span>{\r\n    <span class=\"hljs-keyword\">auto<\/span> bindFunc1 = bind(TestFunc, <span class=\"hljs-built_in\">std<\/span>::placeholders::_1, <span class=\"hljs-string\">'A'<\/span>, <span class=\"hljs-number\">100.1<\/span>);\r\n    bindFunc1(<span class=\"hljs-number\">10<\/span>);\r\n\r\n    <span class=\"hljs-built_in\">cout<\/span> &lt;&lt; <span class=\"hljs-string\">\"=================================\\n\"<\/span>;\r\n\r\n    <span class=\"hljs-keyword\">auto<\/span> bindFunc2 = bind(TestFunc, <span class=\"hljs-built_in\">std<\/span>::placeholders::_2, <span class=\"hljs-built_in\">std<\/span>::placeholders::_1, <span class=\"hljs-number\">100.1<\/span>);\r\n    bindFunc2(<span class=\"hljs-string\">'B'<\/span>, <span class=\"hljs-number\">10<\/span>);\r\n\r\n    <span class=\"hljs-built_in\">cout<\/span> &lt;&lt; <span class=\"hljs-string\">\"=================================\\n\"<\/span>;\r\n\r\n    <span class=\"hljs-keyword\">auto<\/span> bindFunc3 = bind(TestFunc, <span class=\"hljs-built_in\">std<\/span>::placeholders::_2, <span class=\"hljs-built_in\">std<\/span>::placeholders::_3, <span class=\"hljs-built_in\">std<\/span>::placeholders::_1);\r\n    bindFunc3(<span class=\"hljs-number\">100.1<\/span>, <span class=\"hljs-number\">30<\/span>, <span class=\"hljs-string\">'C'<\/span>);\r\n\r\n    <span class=\"hljs-keyword\">return<\/span> <span class=\"hljs-number\">0<\/span>;\r\n}\r\n<\/code><\/pre>\n<p>\u4e0a\u9762\u8fd9\u6bb5\u4ee3\u7801\u4e3b\u8981\u8bf4\u7684\u662fbind\u4e2dstd::placeholders\u7684\u4f7f\u7528\u3002 std::placeholders\u662f\u4e00\u4e2a\u5360\u4f4d\u7b26\u3002\u5f53\u4f7f\u7528bind\u751f\u6210\u4e00\u4e2a\u65b0\u7684\u53ef\u8c03\u7528\u5bf9\u8c61\u65f6\uff0cstd::placeholders\u8868\u793a\u65b0\u7684\u53ef\u8c03\u7528\u5bf9\u8c61\u7684\u7b2c \u51e0\u4e2a\u53c2\u6570\u548c\u539f\u51fd\u6570\u7684\u7b2c\u51e0\u4e2a\u53c2\u6570\u8fdb\u884c\u5339\u914d\uff0c\u8fd9\u4e48\u8bf4\u6709\u70b9\u7ed5\u3002\u6bd4\u5982\uff1a<\/p>\n<pre><code class=\"language-cpp hljs\"><span class=\"hljs-keyword\">auto<\/span> bindFunc3 = bind(TestFunc, <span class=\"hljs-built_in\">std<\/span>::placeholders::_2, <span class=\"hljs-built_in\">std<\/span>::placeholders::_3, <span class=\"hljs-built_in\">std<\/span>::placeholders::_1);\r\n\r\nbindFunc3(<span class=\"hljs-number\">100.1<\/span>, <span class=\"hljs-number\">30<\/span>, <span class=\"hljs-string\">'C'<\/span>);\r\n<\/code><\/pre>\n<p>\u53ef\u4ee5\u770b\u5230\uff0c\u5728bind\u7684\u65f6\u5019\uff0c\u7b2c\u4e00\u4e2a\u4f4d\u7f6e\u662fTestFunc\uff0c\u9664\u4e86\u8fd9\u4e2a\uff0c\u53c2\u6570\u7684\u7b2c\u4e00\u4e2a\u4f4d\u7f6e\u4e3a\u5360\u4f4d\u7b26std::placeholders::_2\uff0c\u8fd9\u5c31\u8868\u793a\uff0c\u8c03\u7528bindFunc3\u7684\u65f6\u5019\uff0c\u5b83\u7684\u7b2c\u4e8c\u4e2a\u53c2\u6570\u548cTestFunc\u7684\u7b2c\u4e00\u4e2a\u53c2\u6570\u5339\u914d\uff0c\u4ee5\u6b64\u7c7b\u63a8\u3002<\/p>\n<p>\u4ee5\u4e0b\u662f\u4f7f\u7528std::bind\u7684\u4e00\u4e9b\u9700\u8981\u6ce8\u610f\u7684\u5730\u65b9\uff1a<\/p>\n<ul>\n<li>bind\u9884\u5148\u7ed1\u5b9a\u7684\u53c2\u6570\u9700\u8981\u4f20\u5177\u4f53\u7684\u53d8\u91cf\u6216\u503c\u8fdb\u53bb\uff0c\u5bf9\u4e8e\u9884\u5148\u7ed1\u5b9a\u7684\u53c2\u6570\uff0c\u662fpass-by-value\u7684\uff1b<\/li>\n<li>\u5bf9\u4e8e\u4e0d\u4e8b\u5148\u7ed1\u5b9a\u7684\u53c2\u6570\uff0c\u9700\u8981\u4f20std::placeholders\u8fdb\u53bb\uff0c\u4ece_1\u5f00\u59cb\uff0c\u4f9d\u6b21\u9012\u589e\u3002placeholder\u662fpass-by-reference\u7684\uff1b<\/li>\n<li>bind\u7684\u8fd4\u56de\u503c\u662f\u53ef\u8c03\u7528\u5b9e\u4f53\uff0c\u53ef\u4ee5\u76f4\u63a5\u8d4b\u7ed9std::function\u5bf9\u8c61\uff1b<\/li>\n<li>\u5bf9\u4e8e\u7ed1\u5b9a\u7684\u6307\u9488\u3001\u5f15\u7528\u7c7b\u578b\u7684\u53c2\u6570\uff0c\u4f7f\u7528\u8005\u9700\u8981\u4fdd\u8bc1\u5728\u53ef\u8c03\u7528\u5b9e\u4f53\u8c03\u7528\u4e4b\u524d\uff0c\u8fd9\u4e9b\u53c2\u6570\u662f\u53ef\u7528\u7684\uff1b<\/li>\n<li>\u7c7b\u7684this\u53ef\u4ee5\u901a\u8fc7\u5bf9\u8c61\u6216\u8005\u6307\u9488\u6765\u7ed1\u5b9a\u3002<\/li>\n<\/ul>\n<h4 id=\"\u4e3a\u4ec0\u4e48\u8981\u7528stdbind\">\u4e3a\u4ec0\u4e48\u8981\u7528std::bind<\/h4>\n<p>\u5f53\u6211\u4eec\u538c\u5026\u4e86\u4f7f\u7528<code>std::bind1st<\/code>\u548c<code>std::bind2nd<\/code>\u7684\u65f6\u5019\uff0c\u73b0\u5728\u6709\u4e86<code>std::bind<\/code>\uff0c\u4f60\u5b8c\u5168\u53ef\u4ee5\u653e\u5f03\u4f7f\u7528<code>std::bind1st<\/code>\u548c<code>std::bind2nd<\/code>\u4e86\u3002<code>std::bind<\/code>\u7ed1\u5b9a\u7684\u53c2\u6570\u7684\u4e2a\u6570\u4e0d\u53d7\u9650\u5236\uff0c\u7ed1\u5b9a\u7684\u5177\u4f53\u54ea\u4e9b\u53c2\u6570\u4e5f\u4e0d\u53d7\u9650\u5236\uff0c\u7531\u7528\u6237\u6307\u5b9a\uff0c\u8fd9\u4e2abind\u624d\u662f\u771f\u6b63\u610f\u4e49\u4e0a\u7684\u7ed1\u5b9a\u3002<\/p>\n<p>\u5728Cocos2d-x\u4e2d\uff0c\u6211\u4eec\u53ef\u4ee5\u770b\u5230\uff0c\u4f7f\u7528<code>std::bind<\/code>\u751f\u6210\u4e00\u4e2a\u53ef\u8c03\u7528\u5bf9\u8c61\uff0c\u8fd9\u4e2a\u5bf9\u8c61\u53ef\u4ee5\u76f4\u63a5\u8d4b\u503c\u7ed9<code>std::function<\/code>\u5bf9\u8c61\uff1b\u5728\u7c7b\u4e2d\u6709\u4e00\u4e2a<code>std::function<\/code>\u7684\u53d8\u91cf\uff0c\u8fd9\u4e2a<code>std::function<\/code>\u7531<code>std::bind<\/code>\u6765\u8d4b\u503c\uff0c\u800c<code>std::bind<\/code>\u7ed1\u5b9a\u7684\u53ef\u8c03\u7528\u5bf9\u8c61\u53ef\u4ee5\u662fLambda\u8868\u8fbe\u5f0f\u6216\u8005\u7c7b\u6210\u5458\u51fd\u6570\u7b49\u53ef\u8c03\u7528\u5bf9\u8c61\uff0c\u8fd9\u4e2a\u662fCocos2d-x\u4e2d\u7684\u4e00\u822c\u7528\u6cd5\u3002<\/p>\n<p>\u4ee5\u540e\u9047\u5230\u4e86\u201c\u5947\u8469\u201d\u7528\u6cd5\u518d\u7ee7\u7eed\u603b\u7ed3\u4e86\uff0c\u4e00\u6b21\u4e5f\u603b\u7ed3\u4e0d\u5b8c\u7684\u3002<\/p>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>\u539f\u6587\u5730\u5740 \u770b\u770b\u8fd9\u6bb5\u4ee3\u7801 \u8fd9\u51e0\u5929\u5b66\u4e60Coc<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[],"tags":[119],"class_list":["post-4034","post","type-post","status-publish","format-standard","hentry","tag-03-"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/4034","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/comments?post=4034"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/4034\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=4034"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=4034"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=4034"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}