无法将MySqlDateTime转换为System.Date - 不为null [英] Can't convert MySqlDateTime to System.Date - not null

问题描述

使用MySqlData（Connector / Net）和MySql数据库和VB.NET



以下

Am using MySqlData (Connector/Net) with a MySql database and VB.NET

The following

Dim objConn As New MySqlConnection
Dim objCmd As New MySqlCommand
Dim objDA As New MySqlDataAdapter
Dim ds As DataSet
Dim sb As New StringBuilder
Dim d As Date
Try
    objConn.ConnectionString = "server=localhost;database=xxx;uid=xxx;pwd=xxx;AllowZeroDateTime=True;ConvertZeroDateTime=True"
    objConn.Open()
    ds = New DataSet("MyDataSet")
    objDA.SelectCommand = New MySqlCommand
    objDA.SelectCommand.Connection = objConn
    objDA.SelectCommand.CommandText = "select datecolumn from datatable where ID = 1"
    objDA.Fill(ds, "tbl")
    objConn.Close()
    d = CDate(ds.Tables("tbl").Rows(0)("datecolumn"))
    sb.Append(String.Format("{0:dd-MMM-yyyy}", d))
Catch ex As Exception
    If objConn.State = ConnectionState.Open Then objConn.Close()
    sb.Append(ex.Message)
End Try

产生错误

yields the error

Conversion from type 'MySqlDateTime' to type 'Date' is not valid.

NB - datecolumn值不是空值，而是有效的日期/时间值。

WTF正在进行中？每次我尝试谷歌这一切我得到的是与处理NULL值有关的答案。如何在我的代码中使用此MySqlDateTime？即将它转移到System.Date值？

NB - the datecolumn value is NOT a null value, but a valid date/time value.
WTF is going on? Every time I try to google this all I get are answers relating to handling NULL values. How can I work with this MySqlDateTime in my code? i.e. convet it to a System.Date value?

推荐答案

您可能遇到与此处 [ ^ ]

try

try

Dim d2 As DateTime = DateTime.Parse(ds.Tables("tbl").Rows(0)("datecolumn").ToString())
sb.Append(String.Format("{0:dd-MMM-yyyy}", d2))

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