How to change the background color of a Passwordbox for WPF/C# -

i have class called passwordvalidationrules

it's simple class

    public bool validatepasswordrules(string text)     {         regex regex = new regex(@"^(?=.{8}$)(?=.*[a-z])(?=.*[0-9])(?=.*[,@#$])");         bool isvalid = regex.ismatch(text);         if (isvalid)         {             return true;         }         else         {                             return false;         }     } 

i want check rules user types passwordbox.

i have trigger when 8 characters typed , background change green if "true", otherwise should have red background.

i barely know wpf, have done way,

first create password validation extension string

public static class validate {     public static bool validatepassword(this string password)     {         regex regex = new regex(@"^(?=.{8}$)(?=.*[a-z])(?=.*[0-9])(?=.*[,@#$])");         bool isvalid = regex.ismatch(password);         if (isvalid)         {             return true;         }         else         {             return false;         }     } } 

then in passwordchanged event of passwordbox,

private void text_passwordchanged(object sender, routedeventargs e) {     if (text.password.length >= 8)     {       if (text.password.validatepassword())       {          text.background = new solidcolorbrush(color.fromrgb(0, 255, 0));       }       else          text.background = new solidcolorbrush(color.fromrgb(255, 0, 0));     }     else       text.background = systemcolors.windowbrush;  }