{"id":2994,"date":"2025-03-19T21:45:08","date_gmt":"2025-03-19T13:45:08","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=2994"},"modified":"2025-03-19T21:45:08","modified_gmt":"2025-03-19T13:45:08","slug":"php-for-%e5%be%aa%e7%8e%af%e8%af%a6%e8%a7%a3","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/03\/19\/php-for-%e5%be%aa%e7%8e%af%e8%af%a6%e8%a7%a3\/","title":{"rendered":"PHP for \u5faa\u73af\u8be6\u89e3"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">1. \u4ec0\u4e48\u662f <code>for<\/code> \u5faa\u73af\uff1f<\/h2>\n\n\n\n<p><code>for<\/code> \u5faa\u73af\u662f\u4e00\u79cd <strong>\u5faa\u73af\u6b21\u6570\u786e\u5b9a<\/strong> \u7684\u5faa\u73af\u7ed3\u6784\uff0c\u901a\u5e38\u7528\u4e8e <strong>\u5df2\u77e5\u9700\u8981\u6267\u884c\u591a\u5c11\u6b21<\/strong> \u7684\u60c5\u51b5\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udccc \u8bed\u6cd5\uff1a<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>for (\u521d\u59cb\u5316; \u6761\u4ef6; \u9012\u589e\/\u9012\u51cf) {\n    \/\/ \u4ee3\u7801\u5757\n}<\/code><\/pre>\n\n\n\n<p>\u2705 <strong>\u53c2\u6570\u89e3\u6790<\/strong>\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>\u521d\u59cb\u5316<\/code>\uff1a\u8bbe\u7f6e <strong>\u5faa\u73af\u53d8\u91cf\u7684\u521d\u59cb\u503c<\/strong>\uff08\u4ec5\u6267\u884c\u4e00\u6b21\uff09<\/li>\n\n\n\n<li><code>\u6761\u4ef6<\/code>\uff1a\u6bcf\u6b21\u5faa\u73af\u524d\u90fd\u4f1a\u68c0\u67e5\uff0c<strong>\u4e3a <code>true<\/code> \u5219\u6267\u884c\u5faa\u73af<\/strong>\uff0c\u5426\u5219\u7ec8\u6b62<\/li>\n\n\n\n<li><code>\u9012\u589e\/\u9012\u51cf<\/code>\uff1a\u6bcf\u6b21\u5faa\u73af\u540e <strong>\u66f4\u65b0\u53d8\u91cf<\/strong>\uff0c\u907f\u514d\u6b7b\u5faa\u73af<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">2. <code>for<\/code> \u5faa\u73af\u793a\u4f8b<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>\u793a\u4f8b 1\uff1a\u6253\u5370 1-5<\/strong><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\nfor ($i = 1; $i &lt;= 5; $i++) {\n    echo \"\u5f53\u524d\u6570\u503c\uff1a\" . $i . \"&lt;br&gt;\";\n}\n?&gt;<\/code><\/pre>\n\n\n\n<p>\ud83d\udd39 <strong>\u89e3\u6790<\/strong>\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><code>$i = 1<\/code>\uff08\u521d\u59cb\u5316\uff09<\/li>\n\n\n\n<li><code>while ($i &lt;= 5)<\/code> <strong>\u5224\u65ad\u6761\u4ef6<\/strong>\uff0c\u6ee1\u8db3\u6267\u884c\u5faa\u73af\u4f53<\/li>\n\n\n\n<li><code>$i++<\/code>\uff08\u6bcf\u6b21\u5faa\u73af\u9012\u589e\uff09<\/li>\n\n\n\n<li>\u76f4\u5230 <code>$i > 5<\/code>\uff0c\u5faa\u73af\u7ec8\u6b62<\/li>\n<\/ol>\n\n\n\n<p>\ud83d\udd39 <strong>\u8f93\u51fa\u7ed3\u679c<\/strong>\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u5f53\u524d\u6570\u503c\uff1a1\n\u5f53\u524d\u6570\u503c\uff1a2\n\u5f53\u524d\u6570\u503c\uff1a3\n\u5f53\u524d\u6570\u503c\uff1a4\n\u5f53\u524d\u6570\u503c\uff1a5<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">3. <code>for<\/code> \u5faa\u73af\u7684\u5e38\u89c1\u5e94\u7528<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>\u793a\u4f8b 2\uff1a\u7d2f\u52a0\u6c42\u548c<\/strong><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\n$sum = 0;\nfor ($i = 1; $i &lt;= 100; $i++) {\n    $sum += $i;\n}\necho \"1 \u5230 100 \u7684\u603b\u548c\u662f\uff1a\" . $sum;\n?&gt;<\/code><\/pre>\n\n\n\n<p>\ud83d\udd39 <strong>\u8f93\u51fa<\/strong>\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>1 \u5230 100 \u7684\u603b\u548c\u662f\uff1a5050<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>\u793a\u4f8b 3\uff1a\u904d\u5386\u6570\u7ec4<\/strong><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\n$fruits = &#91;\"\u82f9\u679c\", \"\u9999\u8549\", \"\u6a58\u5b50\", \"\u8461\u8404\"];\nfor ($i = 0; $i &lt; count($fruits); $i++) {\n    echo \"\u6c34\u679c\uff1a\" . $fruits&#91;$i] . \"&lt;br&gt;\";\n}\n?&gt;<\/code><\/pre>\n\n\n\n<p>\ud83d\udd39 <strong>\u8f93\u51fa<\/strong>\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u6c34\u679c\uff1a\u82f9\u679c\n\u6c34\u679c\uff1a\u9999\u8549\n\u6c34\u679c\uff1a\u6a58\u5b50\n\u6c34\u679c\uff1a\u8461\u8404<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>\u793a\u4f8b 4\uff1a\u5012\u5e8f\u5faa\u73af<\/strong><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\nfor ($i = 10; $i &gt;= 1; $i--) {\n    echo $i . \" \";\n}\n?&gt;<\/code><\/pre>\n\n\n\n<p>\ud83d\udd39 <strong>\u8f93\u51fa<\/strong>\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>10 9 8 7 6 5 4 3 2 1<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">4. <code>for<\/code> \u5faa\u73af\u7684\u9ad8\u7ea7\u7528\u6cd5<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>\u793a\u4f8b 5\uff1a\u5d4c\u5957 <code>for<\/code><\/strong><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\nfor ($i = 1; $i &lt;= 3; $i++) {\n    for ($j = 1; $j &lt;= 3; $j++) {\n        echo \"($i, $j) \";\n    }\n    echo \"&lt;br&gt;\";\n}\n?&gt;<\/code><\/pre>\n\n\n\n<p>\ud83d\udd39 <strong>\u8f93\u51fa<\/strong>\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>(1, 1) (1, 2) (1, 3) \n(2, 1) (2, 2) (2, 3) \n(3, 1) (3, 2) (3, 3)<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>\u793a\u4f8b 6\uff1a\u4e5d\u4e5d\u4e58\u6cd5\u8868<\/strong><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\nfor ($i = 1; $i &lt;= 9; $i++) {\n    for ($j = 1; $j &lt;= $i; $j++) {\n        echo \"$j x $i = \" . ($j * $i) . \"\\t\";\n    }\n    echo \"&lt;br&gt;\";\n}\n?&gt;<\/code><\/pre>\n\n\n\n<p>\ud83d\udd39 <strong>\u8f93\u51fa<\/strong>\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>1 x 1 = 1  \n1 x 2 = 2  2 x 2 = 4  \n1 x 3 = 3  2 x 3 = 6  3 x 3 = 9  \n...<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">5. <code>for<\/code> vs <code>while<\/code> vs <code>do...while<\/code><\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th><\/th><th><code>for<\/code><\/th><th><code>while<\/code><\/th><th><code>do...while<\/code><\/th><\/tr><\/thead><tbody><tr><td><strong>\u9002\u7528\u573a\u666f<\/strong><\/td><td><strong>\u5faa\u73af\u6b21\u6570\u786e\u5b9a<\/strong><\/td><td><strong>\u5faa\u73af\u6b21\u6570\u4e0d\u786e\u5b9a<\/strong><\/td><td><strong>\u81f3\u5c11\u6267\u884c\u4e00\u6b21<\/strong><\/td><\/tr><tr><td><strong>\u6267\u884c\u987a\u5e8f<\/strong><\/td><td>\u521d\u59cb\u5316 \u2192 \u5224\u65ad \u2192 \u6267\u884c \u2192 \u9012\u589e<\/td><td>\u5224\u65ad \u2192 \u6267\u884c<\/td><td>\u5148\u6267\u884c \u2192 \u518d\u5224\u65ad<\/td><\/tr><tr><td><strong>\u662f\u5426\u4e00\u5b9a\u6267\u884c<\/strong><\/td><td>\u274c \u5426<\/td><td>\u274c \u5426<\/td><td>\u2705 \u662f<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p>\u2705 <strong>\u9009\u62e9\u6307\u5357<\/strong>\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u5faa\u73af\u6b21\u6570\u786e\u5b9a<\/strong> \u279d <code>for<\/code><\/li>\n\n\n\n<li><strong>\u5faa\u73af\u6b21\u6570\u4e0d\u786e\u5b9a<\/strong> \u279d <code>while<\/code><\/li>\n\n\n\n<li><strong>\u81f3\u5c11\u6267\u884c\u4e00\u6b21<\/strong> \u279d <code>do...while<\/code><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">6. <code>for<\/code> \u5faa\u73af\u5e38\u89c1\u9519\u8bef &amp; \u89e3\u51b3\u65b9\u6848<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">\u274c <strong>\u9519\u8bef 1\uff1a\u6b7b\u5faa\u73af<\/strong><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\nfor ($i = 1; $i &gt; 0; $i++) {  \/\/ \u6ca1\u6709\u7ec8\u6b62\u6761\u4ef6\n    echo $i . \"&lt;br&gt;\";\n}\n?&gt;<\/code><\/pre>\n\n\n\n<p>\u26a0\ufe0f <strong>\u95ee\u9898<\/strong>\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>$i<\/code> <strong>\u4e00\u76f4\u9012\u589e<\/strong>\uff0c\u5bfc\u81f4 <strong>\u65e0\u9650\u5faa\u73af<\/strong>\uff0c\u7a0b\u5e8f\u5d29\u6e83\u3002<\/li>\n<\/ul>\n\n\n\n<p>\u2705 <strong>\u4fee\u6b63<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\nfor ($i = 1; $i &lt;= 10; $i++) {\n    echo $i . \"&lt;br&gt;\";\n}\n?&gt;<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">\u274c <strong>\u9519\u8bef 2\uff1a\u53d8\u91cf\u672a\u521d\u59cb\u5316<\/strong><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\nfor (; $i &lt;= 5; $i++) {  \/\/ \u7f3a\u5c11\u521d\u59cb\u5316\n    echo $i . \"&lt;br&gt;\";\n}\n?&gt;<\/code><\/pre>\n\n\n\n<p>\u26a0\ufe0f <strong>\u95ee\u9898<\/strong>\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>$i<\/code> <strong>\u672a\u521d\u59cb\u5316<\/strong>\uff0c\u53ef\u80fd\u5bfc\u81f4 <code>Undefined variable<\/code> \u9519\u8bef\u3002<\/li>\n<\/ul>\n\n\n\n<p>\u2705 <strong>\u4fee\u6b63<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;?php\nfor ($i = 1; $i &lt;= 5; $i++) {\n    echo $i . \"&lt;br&gt;\";\n}\n?&gt;<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">7. \u7ec3\u4e60\u9898<\/h2>\n\n\n\n<p>\ud83d\udcdd <strong>\u8bf7\u5c1d\u8bd5\u5b8c\u6210\u4ee5\u4e0b\u4efb\u52a1<\/strong>\uff1a<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"> <strong>\u7ec3\u4e60 1\uff1a\u8f93\u51fa 1 \u5230 10 \u7684\u5076\u6570<\/strong><\/h3>\n\n\n\n<p><strong>\u63d0\u793a<\/strong>\uff1a\u4f7f\u7528 <code>if ($i % 2 == 0)<\/code><\/p>\n\n\n\n<h3 class=\"wp-block-heading\"> <strong>\u7ec3\u4e60 2\uff1a\u8ba1\u7b97 1 \u5230 50 \u7684\u5947\u6570\u548c<\/strong><\/h3>\n\n\n\n<p><strong>\u63d0\u793a<\/strong>\uff1a\u7d2f\u52a0\u5947\u6570 <code>if ($i % 2 != 0)<\/code><\/p>\n\n\n\n<h3 class=\"wp-block-heading\"> <strong>\u7ec3\u4e60 3\uff1a\u751f\u6210 5 \u4e2a\u968f\u673a\u6570\u5e76\u8f93\u51fa<\/strong><\/h3>\n\n\n\n<p><strong>\u63d0\u793a<\/strong>\uff1a<code>rand(1, 100)<\/code><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\ud83d\udd17 \u76f8\u5173\u53c2\u8003\u94fe\u63a5<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/www.php.net\/manual\/en\/control-structures.for.php\">PHP for \u5b98\u65b9\u6587\u6863<\/a><\/li>\n<\/ul>\n\n\n\n<p>\u66f4\u591a\u8be6\u7ec6\u5185\u5bb9\u8bf7\u5173\u6ce8\u5176\u4ed6\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>1. \u4ec0\u4e48\u662f for \u5faa\u73af\uff1f for \u5faa\u73af\u662f\u4e00\u79cd \u5faa\u73af\u6b21\u6570\u786e\u5b9a \u7684\u5faa\u73af\u7ed3\u6784\uff0c\u901a\u5e38\u7528\u4e8e \u5df2\u77e5\u9700\u8981\u6267\u884c\u591a\u5c11\u6b21 \u7684\u60c5 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":2995,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[80],"tags":[],"class_list":["post-2994","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-php"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/2994","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=2994"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/2994\/revisions"}],"predecessor-version":[{"id":2996,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/2994\/revisions\/2996"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media\/2995"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=2994"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=2994"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=2994"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}