mysql - vb.net 更新用户按钮在使用 mysql 时不起作用

Question

我一直在与管理人员一起制作一个项目，在发布时我解决了很多问题，但我无法解决这个问题。当我输入新信息(例如用户未更新的新密码)时，我想更新用户。什么也没做。我该如何修复它？有什么问题吗？

Imports MySql.Data.MySqlClient

公共(public)类DeathLairAdminControlPanel 将 MySqlConn 调暗为 MySqlConnection 将 MySqlCmd 调暗为 MySqlCommand 调暗 dbDT 作为新数据表

Public Property AUsernameHomePass As String
Private Sub DeathLairAdminControlPanel_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    LabelALoggedIn.Text = AUsernameHomePass
End Sub

Private Sub ButtonUpdateU_Click(sender As Object, e As EventArgs) Handles ButtonUpdateU.Click
    If TextBoxNUsern.Text = "" Or TextBoxNEmail.Text = "" Or TextBoxNPass.Text = "" Or TextBoxNPhone.Text = "" Then
        MessageBox.Show("Please don't leave empty areas.", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
    ElseIf TextBoxNUsern.Text.Length < 4 Then
        MessageBox.Show("Username too short.", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
    ElseIf TextBoxNEmail.Text.Length < 8 Then
        MessageBox.Show("Email cant be that short. IT MUST BE VALID!.", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
    ElseIf TextBoxNPass.Text.Length < 6 Then
        MessageBox.Show("Password can't be that short. Make it longer and secure.", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
    ElseIf TextBoxNPhone.Text.Length < 6 Then
        MessageBox.Show("Phone number can't be that short. IT MUST BE VALID.", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
    ElseIf System.Text.RegularExpressions.Regex.IsMatch(TextBoxNUsern.Text, "^[A-Za-z0-9]+$") And System.Text.RegularExpressions.Regex.IsMatch(TextBoxNPass.Text, "^[A-Za-z0-9.]+$") And System.Text.RegularExpressions.Regex.IsMatch(TextBoxNEmail.Text, "\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*") And System.Text.RegularExpressions.Regex.IsMatch(TextBoxNPhone.Text, "^\+[0-9()-+ ]+$") And System.Text.RegularExpressions.Regex.IsMatch(TextBoxNCity.Text, "^[A-Za-z ]+$") Then

        MySqlConn = New MySqlConnection
        MySqlConn.ConnectionString =
            "server=localhost;userid=root;password=HIDDEN;database=syscore"
        Dim MySqlRea As MySqlDataReader

        Try
            MySqlConn.Open()
            Dim Query As String
            Query = "update syscore.normaluser set nusername='" & TextBoxNUsern.Text & "',nemail='" & TextBoxNEmail.Text & "',npass='" & TextBoxNPass.Text & "',nphone='" & TextBoxNPhone.Text & "',ncity='" & TextBoxNCity.Text & "' where nusername='" & TextBoxNUsern.Text & "'"
            MySqlCmd = New MySqlCommand(Query, MySqlConn)
            MySqlRea = MySqlCmd.ExecuteReader

            MessageBox.Show("User has been updated.", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
            MySqlConn.Close()
        Catch ex As MySqlException
            MessageBox.Show(ex.Message)
        Finally
            MySqlConn.Dispose()
        End Try
    End If
    loaddatabase_table()
End Sub

Private Sub ButtonDeleteU_Click(sender As Object, e As EventArgs) Handles ButtonDeleteU.Click
        MySqlConn = New MySqlConnection
        MySqlConn.ConnectionString =
            "server=localhost;userid=root;password=Hidden;database=syscore"
        Dim MySqlRea As MySqlDataReader

        Try
            MySqlConn.Open()
            Dim Query As String
        Query = "delete from syscore.normaluser where nusername='" & TextBoxNUsern.Text & "'"
            MySqlCmd = New MySqlCommand(Query, MySqlConn)
            MySqlRea = MySqlCmd.ExecuteReader

        MessageBox.Show("User has been deleted.", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
            TextBoxNUsern.Text = ""
            TextBoxNEmail.Text = ""
            TextBoxNPass.Text = ""
            TextBoxNPhone.Text = ""
            TextBoxNCity.Text = ""
            MySqlConn.Close()
        Catch ex As MySqlException
            MessageBox.Show(ex.Message)
        Finally
            MySqlConn.Dispose()
        End Try
    loaddatabase_table()
End Sub

Private Sub loaddatabase_table()

    MySqlConn = New MySqlConnection
    MySqlConn.ConnectionString =
        "server=localhost;userid=root;password=Hidden;database=syscore"
    Dim MySqlDAd As New MySqlDataAdapter
    Dim dbDataSet As New DataTable
    Dim bSource As New BindingSource

    Try
        MySqlConn.Open()
        Dim Query As String
        Query = "select * from syscore.normaluser"
        MySqlCmd = New MySqlCommand(Query, MySqlConn)
        MySqlDAd.SelectCommand = MySqlCmd
        MySqlDAd.Fill(dbDataSet)
        dbDT = dbDataSet
        bSource.DataSource = dbDataSet
        DataGridView1.DataSource = bSource
        MySqlDAd.Update(dbDataSet)
        TextBoxNUsern.Text = ""
        TextBoxNEmail.Text = ""
        TextBoxNPass.Text = ""
        TextBoxNPhone.Text = ""
        TextBoxNCity.Text = ""
        MySqlConn.Close()
    Catch ex As MySqlException
        MessageBox.Show(ex.Message)
    Finally
        MySqlConn.Dispose()
    End Try
End Sub
Private Sub ButtonLDB_Click(sender As Object, e As EventArgs) Handles ButtonLDB.Click
    MySqlConn = New MySqlConnection
    MySqlConn.ConnectionString =
        "server=localhost;userid=root;password=Hidden;database=syscore"
    Dim MySqlDAd As New MySqlDataAdapter
    Dim dbDataSet As New DataTable
    Dim bSource As New BindingSource

    Try
        MySqlConn.Open()
        Dim Query As String
        Query = "select * from syscore.normaluser"
        MySqlCmd = New MySqlCommand(Query, MySqlConn)
        MySqlDAd.SelectCommand = MySqlCmd
        MySqlDAd.Fill(dbDataSet)
        dbDT = dbDataSet
        bSource.DataSource = dbDataSet
        DataGridView1.DataSource = bSource
        MySqlDAd.Update(dbDataSet)
        TextBoxNUsern.Text = ""
        TextBoxNEmail.Text = ""
        TextBoxNPass.Text = ""
        TextBoxNPhone.Text = ""
        TextBoxNCity.Text = ""
        MySqlConn.Close()
    Catch ex As MySqlException
        MessageBox.Show(ex.Message)
    Finally
        MySqlConn.Dispose()
    End Try
    loaddatabase_table()
End Sub

Private Sub DataGridView1_CellContentClick(sender As Object, e As DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick
    If e.RowIndex >= 0 Then
        Dim gridrow As DataGridViewRow
        gridrow = Me.DataGridView1.Rows(e.RowIndex)

        TextBoxNUsern.Text = gridrow.Cells("nusername").Value.ToString
        TextBoxNEmail.Text = gridrow.Cells("nemail").Value.ToString
        TextBoxNPass.Text = gridrow.Cells("npass").Value.ToString
        TextBoxNPhone.Text = gridrow.Cells("nphone").Value.ToString
        TextBoxNCity.Text = gridrow.Cells("ncity").Value.ToString
    End If
End Sub

Private Sub TextBoxSdbgrid_TextChanged(sender As Object, e As EventArgs) Handles TextBoxSdbgrid.TextChanged
    Dim DV As New DataView(dbDT)
    DV.RowFilter = String.Format("nusername Like '%{0}%'", TextBoxSdbgrid.Text)
    DataGridView1.DataSource = DV
End Sub

Private Sub ReportToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ReportToolStripMenuItem.Click
    MessageBox.Show("To get support or report do it on skype gangsteris33 we are always online until night.", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
End Sub

Private Sub LoginToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles LoginToolStripMenuItem.Click
    Form1.Show()
    TextBoxNCity.Text = ""
    TextBoxNEmail.Text = ""
    TextBoxNPass.Text = ""
    TextBoxNPhone.Text = ""
    TextBoxNUsern.Text = ""
    TextBoxSdbgrid.Text = ""
    Me.Hide()
End Sub

Private Sub ExitToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ExitToolStripMenuItem.Click
    Application.Exit()
End Sub

Private Sub ButtonClearChat_Click(sender As Object, e As EventArgs) Handles ButtonClearChat.Click
    MySqlConn = New MySqlConnection
    MySqlConn.ConnectionString =
        "server=localhost;userid=root;password=Hidden;database=sysinfo"
    Dim MySqlRea As MySqlDataReader

    Try
        MySqlConn.Open()
        Dim Query As String
        Query = "delete from syscore.normaluser"
        MySqlCmd = New MySqlCommand(Query, MySqlConn)
        MySqlRea = MySqlCmd.ExecuteReader

        MessageBox.Show("Chat has been cleaned.", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
        MySqlConn.Close()
    Catch ex As MySqlException
        MessageBox.Show(ex.Message)
    Finally
        MySqlConn.Dispose()
    End Try
End Sub

下课

有人修复了这个错误的代码，粘贴网站时将无法正确粘贴。我希望有人能帮我修复按钮。按下按钮时没有错误，它什么也不做。

Answer 1

更新和插入命令应使用command.ExecuteNonQuery而不是ExecuteReader

  MySqlConn.Open()
  Dim Query As String
  Query = "delete from syscore.normaluser where nusername='" & TextBoxNUsern.Text & "'"
  MySqlCmd = New MySqlCommand(Query, MySqlConn)
  MySqlCmd.ExecuteNonQuery

您还应该考虑使用参数化查询。