private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == 13)
{
string HEX, H;
int DEC = 0, L, X = 0, A;
HEX = textBox1.Text;
L = HEX.Length;
while (L > X)
{
H = HEX.Substring(X, 1);
A = Convert.ToChar(H);
if (A >= 48 && A <= 57)
{
A -= 48;
}
if (A >= 65 && A <= 70)
{
A -= 55;
}
if (A >= 97 && A <= 102)
{
A -= 87;
}
DEC += (int)(A * Math.Pow(16, L - (X++ + 1)));
}
textBox2.Text = DEC.ToString();
}
}
