C#随机颜色和随机字母

public System.Drawing.Color GetRandomColor()
{
Random RandomNum_First = new Random(Guid.NewGuid().GetHashCode());
Random RandomNum_Sencond = new Random(Guid.NewGuid().GetHashCode());

//为了在白色背景上显示，尽量生成深色
int int_Red = RandomNum_First.Next(256);
int int_Green = RandomNum_Sencond.Next(256);
int int_Blue = (int_Red + int_Green > 400) ? 0 : 400 - int_Red - int_Green;
int_Blue = (int_Blue > 255) ? 255 : int_Blue;

return System.Drawing.Color.FromArgb(int_Red, int_Green, int_Blue);
}

public static string GetPageName()
{
string strRand = String.Empty;
System.Random random = new Random(Guid.NewGuid().GetHashCode());
string str = "qwertyuiopasdfghjklmnbvcxz";
for (int i = 0; i < 6; i++)
{
strRand += str[random.Next(0, 25)].ToString();
}
return strRand;
}