public static string MixUp(string str)
{
// var timestamp = DateTime.Now.ToString(TimestampFormat);
var timestamp = Guid.NewGuid().ToString();
var count = str.Length + TimestampLength;
var sbd = new StringBuilder(count);
int j = 0;
int k = 0;
for (int i = 0; i < count; i++)
{
if (j < TimestampLength && k < str.Length)
{
if (i % 2 == 0)
{
sbd.Append(str[k]);
k++;
}
else
{
sbd.Append(timestamp[j]);
j++;
}
}
else if (j >= TimestampLength)
{
sbd.Append(str[k]);
k++;
}
else if (k >= str.Length)
{
break;
// sbd.Append(timestamp[j]);
// j++;
}
}
return sbd.ToString();
}