winforms - C# Button loop? -

i'm trying figure out code i'm supposed write in accordance book (head first c#, 3.5 edition). i'm absolutely baffled loop i'm suppose write. here's i'm suppose do:

make form, have button, check box, , label. when check box marked, button suppose change background color of label. color suppose switch between red , blue when button pressed.

this current code.

namespace secondcolorchangingwindow {     public partial class form1 : form     {         public form1()         {             initializecomponent();         }          private void button1_click(object sender, eventargs e)         {             while (checkbox1.checked == false) // code stop if box isn't checked             {                 messagebox.show("you need check box checked first!");                 break;//stops infinite loop             }             while (checkbox1.checked == true)// code continues "if" box checked.             {                 bool isred = false; // makes "isred" true, since background color default red.                  if (isred == true) // if ground color red, change blue                 {                     label1.backcolor = color.blue; // changes background color blue                     isred = false; //makes "isred" false next time check made, skips while loop                     messagebox.show("the color blue.");//stops program can see color change                 }                 if (isred == false)//if ground color blue, change red                 {                     label1.backcolor = color.red;//makes background color red                     isred = true;//sets "isred" true                     messagebox.show("the color red.");//stops program can see color change.                 }             }         }     } } 

right loops on red. don't understand i'm doing wrong. isn't first code i've written. i've gone integers boolean trying color change, either: makes color once , no other color. or program freezes infinite loops.

you don't need while loop, try if condition , check label color below

   private void button1_click(object sender, eventargs e)     {         if(!checkbox1.checked)         {             messagebox.show("you need check box checked first!");         }         else         {             //changes background color             label1.backcolor = label1.backcolor == color.blue? color.red:color.blue;             messagebox.show("the color " + label1.backcolor.tostring());         }     } 

in current code there no break condition if checkbox1 checked. run infinite loop , freeze program. better add break; after each messagebox.show lines.