尝试使用SqlDataAdapter

Question

我正在尝试在VB.NET中创建一个SQL登录表单，但它并没有真正起作用，表单正在加载，但是当我单击登录时，它只会崩溃并出现异常。有人能告诉我如何解决这个问题吗？

代码：

Imports System.Data.SqlClient

Public Class Form1

Private Sub BTN_LOGIN_Click(sender As Object, e As EventArgs) Handles     BTN_LOGIN.Click

    Dim connection As New SqlConnection("Server= (localdb)\MSSQLLocalDB; Database = TestDB; Integrated Security = true")

    Dim command As New SqlCommand("select * from Table where Username = @username and Password = @password", connection)

    Dim reg As New SqlCommand("INSERT INTO Table (username, password) VALUES (@username, @password)")

    command.Parameters.Add("@username", SqlDbType.VarChar).Value = TextBoxUsername.Text
    command.Parameters.Add("@password", SqlDbType.VarChar).Value = TextBoxPassword.Text

    Dim adapter As New SqlDataAdapter(command)

    Dim data As New DataTable()

    adapter.Fill(data)

    adapter.Dispose()

    If data.Rows.Count() <= 0 Then

        MessageBox.Show("Username Or Password Are Invalid")


    Else

        MessageBox.Show("Login Successfully")

        Dim frm As New Form2()

        Me.Hide()

        frm.Show()

    End If

End Sub

Private Sub BTN_CANCEL_Click(sender As Object, e As EventArgs) Handles BTN_CANCEL.Click

    Me.Close()

End Sub
End Class

表也很好。只是不要谈论表

Answer 1

异常说明：“关键字表附近的语法不正确”。表格的名称是Table吗？这是一个保留关键字。如果是名称，您应该考虑更改它。但是如果你必须使用这个名称，你需要将它嵌入方形支持：

Dim command As New SqlCommand("SELECT * FROM [Table] where Username = @username and Password = @password", connection)