PHP basic tutorial - PHP loop statement
Jul 25, 2016 am 09:00 AM
This section introduces PHP loops to you. PHP loop statements include for, while, do...while, switch, etc. They are probably used the most in actual programming. It is recommended that you have a firm grasp of them.
Welcome to the php loop tutorial page. 1. Break: Indicates the end of the current for, while, do..while, switch process. A number can be given later to indicate which level to retreat to. Such as: <?php //循環(huán)語句示例 //by bbs.it-home.org $i = 0; while(++$i){ switch($i){ case 4: echo "quit to 4.<br>"; break;//跳出switch語句 case 9: echo "quto to 9.<br/>"; break 2; //這里跳了2層,跳出while循環(huán) 這里的數(shù)字不能超過它實際的層數(shù),如果寫成break 3,系統(tǒng)就會報錯。 default: break; } } echo 'Over! $i='.$i; ?> Results: quit to 4. quto to 9. Over! $i=9 2. continue statement: jump out of the remaining code in this loop, and proceed to the next loop when it determines that the condition is true <?php //continue語句 //by bbs.it-home.org for($i=0;$i<13;$i++){ if($i==5){ continue; //跳出本次循環(huán)中的剩余代碼,并判斷本次條件為真的時候進(jìn)行下一次循環(huán) } echo '$i='.$i."<br/>"; } echo "Over"; ?> Results: $i=0 $i=1 $i=2 $i=3 $i=4 $i=6 $i=7 $i=8 $i=9 $i=10 $i=11 $i=12 Over continue can also be followed by numbers: <?php for($i=0;$i<2;$i++){//@ for ($j=1;$j<4;$j++){ if($j==2){ continue 2; //跳出2層循環(huán)后執(zhí)行$i++//@ } echo '$i='.$i.'$j='.$j.'<br/>'; } } echo "Over"; ?> Results: $i=0$j=1 $i=1$j=1 Over 3. goto statement: jumps can only be made in the same file or scope Syntax: goto tag; Label: //..Statement <?php goto a; echo "aa"; a: echo "bb"; ?> Output: bb Thank you for paying attention to the PHP introductory tutorials. This series of PHP basic tutorials will help PHP newbies quickly master the PHP programming language. Programmer's Home will continue to launch PHP-related tutorials for everyone, and I wish you all the best in your learning and progress! |

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