if/switch/while/do while/for/等サイクルおよび判断の簡単な使い方例

 int i = 3;
        //if     ===================================================
        if (i < 2)
            i = 3;
        else
            i = 4;
        Response.Write(i+"
");
        
        
        //if      ，  c#    =，   ==
        i=3;
        if (i == 1)
            Response.Write("1");
        else if (i == 2) Response.Write("2");
        else if (i == 3) Response.Write("3");
        else if (i == 4) Response.Write("4");

        
        //switch    =================================================
        i = 2;
        switch (i)
        { 
            case 1:
            Response.Write("   1  ");
            break;
            case 2:
            Response.Write("   2  ");
            break;
            case 3:
            Response.Write("   3  ");
            break;
            case 4:
            Response.Write("   4  ");
            break;
            default: //   else,       case      break，   break       
            Response.Write("       4    ");
            break;
        }
        
        
        //while        ==========================================
        /*     while       ，    true，     ，      while      ，      ，   false   */
        i = 1;
        while (i < 51)
        { 
        i=i+1;
        }
        Response.Write("
"+i+"
");
        
        
        //do-while   ================================================
        /*               ，  true    ，   false*/
        int j=1;int zyj=0;
            do
            {
             zyj=zyj+j;

            j=j+1;
            }
            while(j<101);
            Response.Write("1+2+3+...+100=" + zyj+"
");
        
        
        //for      ==================================================
        /*
         for(   1;   2;   3)
         *        、       、       
         *    1                   
         */
            for (i = 0; i < 10; i++)
                Response.Write(i+"
======");

        
        //     break/continue/return    =================================
        /*
         break            switch、while、do while、for   
         */

            for (i = 0; i < 10; i++)
                if (i ==5)
                {
                    break;
                }
                else
                    Response.Write(i);