PHP学习笔记2-流程控制

条件控制：if

 <?php
 function getLevel($score){
     if($score>=90){
         return "优秀";
     }elseif($score>=80){
         return "良好";
     }elseif($score>=70){
         return "中等";
     }elseif($score>=60){
         return "及格";
     }else{
         return "差";
     }
 }
 echo getLevel(90);

多分支控制：switch

 <?php
 function getLevel($score){
     switch(intval($score/10)){ //intval()把变量转换成整数类型
         case 10:
         case 9:
             return "优秀";
         case 8:
             return "良好";
         case 7:
             return "中等";
         case 6:
             return "及格";
         default:
             return "差";
     }
 }
 echo getLevel(90);

Break（终止语句执行）

 <?php
 function getLevel($score){
     $result = "差";
     switch($score/10) {
         case 10:
         case 9:
             $result = "优秀";
             break;
         case 8:
             $result = "良好";
             break;
         case 7:
             $result = "中等";
             break;
         case 6:
             $result = "及格";
             break;
         default:
             return "差";
     }
     return $result;
 }
 echo getLevel(90);