Random numbers

I am new to programming and want to know how to generate a random number in C# and be able to output it to a string. I am using the code

[SIZE=2][SIZE=2][COLOR=#0000ff]private[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#0000ff]void[/COLOR][/SIZE][SIZE=2] button1_Click([/SIZE][SIZE=2][COLOR=#0000ff]object[/COLOR][/SIZE][SIZE=2] sender, [/SIZE][SIZE=2][COLOR=#008080]EventArgs[/COLOR][/SIZE][SIZE=2] e)
{

[/SIZE][SIZE=2][COLOR=#008080]Random[/COLOR][/SIZE][SIZE=2] Rnd = [/SIZE][SIZE=2][COLOR=#0000ff]new[/COLOR][/SIZE][SIZE=2] [/SIZE][SIZE=2][COLOR=#008080]Random[/COLOR][/SIZE]SIZE=2;
Rnd.NextDouble();
textBox1.Text = [/SIZE][SIZE=2][COLOR=#008080]Convert[/COLOR][/SIZE][SIZE=2].ToString(Rnd);
}

But when I click my button I get “system random” not a random number.
What am I doing wrong?
Any help you can give me will be appreciated.
Thanks,
Z
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