无法将对象从DBNULL转换为其他类型

Question

我在我的代码中使用了GetOrdinal。代码

mastxtDateEnded_Edit.Text =
        Convert.ToDateTime(cursor.GetValue(cursor.GetOrdinal("DateEnded")))
               .ToString("MM/dd/yyyy"));

Error: object cannot be cast from DBNULL to ther types.   

Answer 1

您可以使用IsDBNull method检查空值：

int index = cursor.GetOrdinal("DateEnded")
mastxtDateEnded_Edit.Text =
  cursor.IsDBNull(index) ?
    String.Empty :
    ((DateTime)(cursor.GetValue(index))).ToString("MM/dd/yyyy");