FLEX程序基本结构--分支结构程序设计

1.if语句

格式:if(表达式) 语句

var a:int=5,b:int=5,max:int;
max=a;
if(max<b) max=b;
trace(max.toString());

2.if.....else语句

格式: if(表达式)

            语句1;

         else
            语句2;

var a:int=5,b:int=10;
if(a>b)
   trace("max:"+a.toString());
else
printf("max:"+b.toString());

3.if...else...if语句

格式:   if(表达式1)

            语句1;

         else if(表达式2)
            语句2;

         else if(表达式m)
            语句m;

         else

             语句n;

4.if语句的嵌套

格式:  if(表达式)

              if语句;

          else

             if语句;

5.switch语句

 格式:  switch(表达式)

{

       case 常量表达式1:语句1; break;

       case 常量表达式2:语句2; break;

       .....

      case 常量表达式n:语句n; break;

      default:  语句n+1; break;

}

                                var a:int=3;
                switch (a)
                {
                    case 1:
                        trace("Monday\n");
                        break;
                    case 2:
                        trace("Tuesday\n");
                        break;
                    case 3:
                        trace("Wednesday\n");
                        break;
                    case 4:
                        trace("Thursday\n");
                        break;
                    case 5:
                        trace("Friday\n");
                        break;
                    case 6:
                        trace("Saturday\n");
                        break;
                    case 7:
                        trace("Sunday\n");
                        break;
                    default:
                        trace("error\n");
                        break;
                }