控制构造（Control Structures）

continue

continue是在反复语句中，停止命令语句的实行并回到反复语句重新评价条件语句的控制构造。

continue的构造

语法构造	说明
for( ; ; ) { if(expr) { stmt1; continue; } stmt2; }	无限反复*for语句，当if语句的表现形式为TRUE时实行命令语句1，依据continue语句移到for*语句的最开始

continue的使用例

<?php
  for($i = 1; ; $i++)  // infinite loop
  {
    if($i % 5)
      continue;        // go to the beginning of for loop
    echo "$i\r\n";     // statement is executed if expression is FALSE
    sleep(1);
  }
?>

[result]  
5
10
15
... (repetition)

continue的选项 continue的后面可以跟进数字。此数据在重叠控制构造中，代表要跳过的控制构造的级别数。

<?php
  $j = 0;
  for($i = 0; ; $i++)                             // infinite loop(level 1)
  {
    sleep(1);
    if($i)
      echo "This is for statement \$i = $i\r\n";  // repeated by continue 2
    while(1)                                      // infinite loop(level 2)
    {
      $j++;
      if(($j % 5) == 0)
        continue 2;                               // go to the beginning of for loop 
      echo "$j, ";
      sleep(1);
    }
  }
?>

[result]  
1, 2, 3, 4, This is for statement $i = 1
6, 7, 8, 9, This is for statement $i = 2
11, 12, 13, 14, This is for statement $i = 3
... (repetition)

< break

switch >