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SQL, VB.Net | 我可以使用什么查询来获取这个值?

[英]SQL, VB.Net | What query can I use grab this value?

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In the above I want it to give me the value of "ID" of the "Username" associated with it.在上面我希望它给我与它相关联的“用户名”的“ID”的值。

Here is the command I tried这是我试过的命令

Dim Query2 = String.Format("SELECT ID FROM account WHERE character = " & UsernameTextBox.Text & " ")
            Command = New MySqlCommand(Query2, mydbcon)
            Dim idtest = reader.Read.ToString
            MsgBox(idtest)

however it is returning "false" what am I doing wrong?但是它返回“假”我做错了什么?

Here is the entire code that I am working on:这是我正在处理的整个代码:

Try
        mydbcon.Open()
        Dim Query As String
        Query = String.Format("SELECT * FROM account WHERE username = '{0}' AND password = '{1}'", Me.UsernameTextBox.Text.Trim(), Me.PasswordTextBox.Text.Trim())
        Dim Command = New MySqlCommand(Query, mydbcon)
        reader = Command.ExecuteReader

        Dim count As Integer
        count = 0
        While reader.Read
            count = count + 1
        End While

        If count = 1 Then
            MessageBox.Show("Username and password are correct")
            Query = String.Format("SELECT username AS ID FROM account WHERE character = " & UsernameTextBox.Text & " ")
            Command = New MySqlCommand(Query, mydbcon)

            My.Settings.LoginID = reader.Read
            MsgBox(My.Settings.LoginID)
        ElseIf count > 1 Then
            MessageBox.Show("Username and password are duplicate")
        Else
            MessageBox.Show("Username and password are wrong")
        End If
        mydbcon.Close()
    Catch ex As MySqlException
        MessageBox.Show(ex.Message)
    Finally
        mydbcon.Dispose()
    End Try

使用 ID 作为别名(因此select username AS anyNameYouWantToAssignToIt ):

Dim Query2 = String.Format("SELECT username AS ID FROM account WHERE character = " & UsernameTextBox.Text & " ")

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