for循环语句
打印金字塔
立即学习“PHP免费学习笔记（深入）”；
完整的金字塔
<span> <span><span> <span> <span>=25<span><span> <span for>(<span>=1;<span><=<span>;<span>++<span><span> <span><span> <span> <span for>(<span>=1;<span><=<span>-<span>;<span>++<span><span> <span echo> ' '<span><span> <span><span> <span><span> <span> <span for>(<span>=1;<span><=<span>*2-1;<span>++<span><span> <span> <span if>(<span>==1 || <span>==<span><span><span> <span echo> '.'<span><span> <span><span> <span else><span><span> <span if>(<span>==1 || <span>==<span>*2-1<span><span> <span echo> '.'<span><span> }<span else><span><span> <span echo> ' '<span><span> <span><span> <span><span> <span><span> <span> <span> <span for><span> <span echo><span> <span><span> <span> <span echo> '<br/>'<span><span> <span> }</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
switch语句：
<span> <span><span><span> <span switch><span> <span case><span> <span echo><span> <span break><span> <span> <span default:><span> <span echo><span> <span break><span> <span><span> <span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
switch选择语句中遇到布尔值时的处理：
<span> <span>=<span true><span><span> <span switch>(<span><span><span> <span case> <span false>: <span> <span echo> "不匹配"<span><span> <span break><span><span> <span><span> <span> <span case> "1": <span> <span echo> "成功匹配"<span><span> <span break><span><span> <span default>: <span> <span echo> "ko"<span><span> <span><span> <span><span><span> <span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
while循环和do..while循环：
<span> <span><span while><span> <span><span> <span while><span> <span echo><span> <span><span> <span><span> <span><span> <span><span> <span do><span> <span echo><span> <span><span> <span><span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
while循环和switch选择语句的结合：
PHP与MySQL程序设计3
下载
本书是全面讲述PHP与MySQL的经典之作，书中不但全面介绍了两种技术的核心特性，还讲解了如何高效地结合这两种技术构建健壮的数据驱动的应用程序。本书涵盖了两种技术新版本中出现的最新特性，书中大量实际的示例和深入的分析均来自于作者在这方面多年的专业经验，可用于解决开发者在实际中所面临的各种挑战。 本书内容全面深入，适合各层次PHP和MySQL开发人员阅读，既是优秀的学习教程，也可用作参考手册。
常量：
<span> <span><span>
<span> <span define>('TAX',200<span><span> <span echo><span tax><span>
<span> <span const> Tab=100<span><span> <span echo> Tab;</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
编写简易计算器：
step1:编写输入界面
<span> <html> <span> <head> <span> <title></title> <span> <span> </head> <span> <body> <span> <span> <form action="CAL.php" method="get"> <span> <input type="text" placeholder="输入一个数" name="num1"> <span> <input type="text" placeholder="输入一个数" name="num2"> <span> <select name="operation"> <span> <option value="+">+</option> <span> <option value="-">-</option> <span> <option value="*">*</option> <span> <option value="/">/</option> <span> </select> <span> <input type="submit" value="计算"> <span> </form> <span> </body> <span> </html></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
step2:写计算后台代码
<span> <?<span php><span> <span>=<span>['num1'<span><span> <span>=<span>['num2'<span><span> <span> <span>=<span>['operation'<span><span> <span>=0<span><span> <span> <span switch>(<span><span><span> <span case> '+': <span> <span>=<span>+<span><span><span> <span break><span><span> <span case> '-': <span> <span>=<span>-<span><span><span> <span break><span><span> <span case> '*': <span> <span>=<span>*<span><span><span> <span break><span><span> <span case> '/': <span> <span>=<span>/<span><span><span> <span break><span><span> <span default>: <span> <span echo> '输入有误'<span><span> <span><span> <span> <span echo> '结果是'.<span><span><span> ?></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
continue语句：跳过本次循环后面的代码。可以指定跳出指定的层数，例如continue 2；表示跳出两层，类似于break 2;
goto语句：和c语言一样，跳转到有标签的代码处，中间的代码不会执行，直接忽略。
<span> <span><span goto><span> <span> <span> <span for>(<span>=0,<span>=50;<span><100;<span>++<span><span> <span while>(<span>--<span><span> <span if>(<span>==17) goto <span end><span><span> <span><span> <span><span> <span echo> 'i=$i'<span><span> <span end>: <span> <span echo> 'i='.<span>.'j='.<span>;</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
