从VB.Net中的SQL表中删除记录 [英] Delete records from SQL table in VB.Net

问题描述

你好朋友，



我试图从我的表中删除记录但是无法这样做。我有窗体，包含插入，更新，删除和保存按钮。我可以插入数据，但我不能删除该表中的特定或任何记录。以下是我的代码。



每当我点击''删除''按钮时，我得到（删除表上的记录时出错...& ex.Message，删除记录）仅限msgbox。



我错过了什么吗？请指教。任何帮助都会很棒。谢谢！

Hello Friends,

I am trying to delete records from my table but unable to do so. I have window form with Insert, Update, Delete and Save button. I can insert data but I can''t delete specific or any records from that table. Below is my code.

Whenever I click ''delete'' button I get ("Error while deleting record on table..." & ex.Message, "Delete Records") msgbox only.

Am I missing something? Please advise. Any help would be great. Thank you!

Private Sub Deletebtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Deletebtn.Click

        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Try
            con.ConnectionString = "Server=USRAG-L-0067215\SQLEXPRESS;Database=Alamo Products_Design Data;Trusted_Connection=True"
            con.Open()
            cmd.Connection = con
           cmd.CommandText = "Delete From Design_ParameterswhereDesignID=@DesignID "
            cmd.Parameters.Add(New SqlParameter("@DesignID", " Am I missing any value here?"))
            cmd.ExecuteNonQuery()
            If MessageBox.Show("Do you really want to Delete this Record?", "Delete", MessageBoxButtons.YesNo, MessageBoxIcon.Warning) = DialogResult.No Then

                MsgBox("Operation Cancelled")

                Exit Sub

            End If
        Catch ex As Exception
            MessageBox.Show("Error while deleting record on table..." & ex.Message, "Delete Records")

        Finally

            con.Close()
        End Try
    End Sub
End Class

推荐答案

'？''代表你的 CommandText 。如果是未命名参数，请参阅如何设置未命名的SQL参数在SqlCommand [ ^ ]。此外，在您的代码中设置了这样的参数？

What the ''?'' stands for in your CommandText. If it is an unnamed parameter, please see "How to set unnamed SQL parameters in SqlCommand"[^]. Moreover where such parameter is set in your code?

这篇关于从VB.Net中的SQL表中删除记录的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！