string str = txtString.EditValue.ToString();
char[] c = str.ToCharArray();
for (int i = 0; i < str.Length; i++)
{
if ((char)str[i] > 'a' && (char)str[i] < 'z')
{
foreach (char l in c)
{
txtLowString.EditValue = string.Format(l.ToString());
}
}
else
{
}