Error converting datetime to string

I am getting an error when I attempt to display a datetime value in a textbox:

My code is:

txtStartDate.Text = rdrGetUserInfo.IsDBNull(14) ? String.Empty : Convert.ToString(rdrGetUserInfo.GetString(14));

The error message is: ex.Mes开发者_如何学编程sage = "Unable to cast object of type 'System.DateTime' to type 'System.String'."

Any ideas how I can resolve this?

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Try:

txtStartDate.Text = rdrGetUserInfo.IsDBNull(14) ? String.Empty : Convert.ToString(rdrGetUserInfo.GetDateTime(14).ToString());