System.Windows.Forms.dll中发生类型为'System.ArgumentException'的未处理异常

Question

I'm really a newbie at programming so do excuse me if my knowledge seems really inadequate. I'm doing a C# project for my school and I'm having problems with my homework, thanks

some codes in here:

using System;
using System.Drawing;


private void button1_Click(object sender, EventArgs e)
{
    child frm2 = new child();
    frm2.ShowDialog();


    int color = 0;
    int i = 0;
    Random rnd = new Random();
    i = rnd.Next(51);

    frm2.BackColor = Color.FromArgb(i*color);
    frm2.ShowDialog();
    if (color == 5)
    {
        color = 0;
    }
}

Answer 1

The problem is this line:

frm2.BackColor = Color.FromArgb(i*color);

Since your i variable is 0 (zero), the resulting color is transparent, and the exact exception message you are getting should be like this:

An unhandled exception of type 'System.ArgumentException' occurred in System.Windows.Forms.dll

Additional information: Control does not support transparent background colors.

In order to fix it, correct your logic for i and color variables and use the following:

frm2.BackColor = Color.FromArgb(255, Color.FromArgb(i * color));

which removes the transparency from the generated color - see Color.FromArgb Method (Int32, Color) .