Window forms

To validate that a textbox contains a string in that format, you can use the DateTime.TryParseExact method in combination with Munesh's format string:

using System.Globalization;

// ...

DateTime dt;

string format fmt = "yyyyMMddHHmmss";

CultureInfo  ci = CultureInfo.InvariantCulture;

DateTimeStyles dts = DateTimeStyles.None;  

bool isValid = DateTime.TryParseExact(textBox1.Text, fmt, ci, dts, out dt);

if(!isValid)

{

   MessageBox.Show("Date/Time is not in the correct format. Please amend");

   textBox1.Focus();

}

else

{

   // do something with 'dt'

}