Question

Protected Sub login_btn_Click(sender As Object, e As EventArgs) Handles login_btn.Click

    Dim connString As String
    Dim connection As SqlConnection
    Dim command As SqlCommand
    Dim sql As String
    connString = "Data Source=.\SQLExpress;Initial Catalog=Suivi_Invst;Integrated Security=True"
    sql = "select NET_ID, Password from User"
    connection = New SqlConnection(connString)

    Try
        connection.Open()
        command = New SqlCommand(sql, connection)
        Dim sqlReader As SqlDataReader = command.ExecuteReader()
        While sqlReader.Read()
            If (Password.Text = sqlReader("Password") And NET_ID.Text = sqlReader("NET_ID")) Then
                Response.Redirect("Creation.aspx")
            End If
        End While

        sqlReader.Close()
        command.Dispose()
        connection.Close()
    Catch ex As Exception
        MsgBox("Can not open connection ! ")
    End Try

End Sub

我总是得到msg信箱说连接无法建立。

我尝试在代码运行的同时打开SQL Server Management Studio，但我什么也没做。

Answer 1

从您的例外文字：

关键字＆＃39;用户＆＃39;
附近的语法不正确

SQL Server中的

User是保留关键字。

基本上不建议创建名称等于保留关键字的表格，但如果您真的需要此名称，则必须在查询中用方括号括起来，如下所示：

select NET_ID, Password from [User]

Answer 2

我可以看到你的连接字符串看起来像是在创建你忘记逃避“\”字符的错误。另外，您可以在try块中移动代码，以便获得特定的错误代码

所以要逃避你可以改变行成为

connString = @“Data Source =。\ SQLExpress; Initial Catalog = Suivi_Invst; Integrated Security = True”;

或

connString =“Data Source =。\\ SQLExpress; Initial Catalog = Suivi_Invst; Integrated Security = True”;

所以请将您的代码更新为：

Protected Sub login_btn_Click（sender As Object，e As EventArgs）处理login_btn.Click

Dim connString As String Dim connection As SqlConnection Dim command As SqlCommand Dim sql As String Try connString = @"Data Source=.\SQLExpress;Initial Catalog=Suivi_Invst;Integrated Security=True" //OR USE BELOW //connString = "Data Source=.\\SQLExpress;Initial Catalog=Suivi_Invst;Integrated Security=True" sql = "select NET_ID, Password from User" connection = New SqlConnection(connString) connection.Open() command = New SqlCommand(sql, connection) Dim sqlReader As SqlDataReader = command.ExecuteReader() While sqlReader.Read() If (Password.Text = sqlReader("Password") And NET_ID.Text = sqlReader("NET_ID")) Then Response.Redirect("Creation.aspx") End If End While sqlReader.Close() command.Dispose() connection.Close() Catch ex As Exception MsgBox("Can not open connection ! ") End Try

End Sub

Answer 3

Protected Sub login_btn_Click(sender As Object, e As EventArgs) Handles login_btn.Click

    Dim connString As String
    Dim connection As SqlConnection
    Dim command As SqlCommand
    Dim sql As String
    connString = "Data Source=.\SQLExpress;Initial Catalog=Suivi_Invst;Integrated Security=True"
//Instead of 
sql = "select NET_ID, Password from User"
//I used this
 sql = "SELECT [NET_ID], [Password] FROM [User] "

它有效

    connection = New SqlConnection(connString)
    Try
        connection.Open()
        command = New SqlCommand(sql, connection)
        Dim sqlReader As SqlDataReader = command.ExecuteReader()
        While sqlReader.Read()
            If (Password.Text = sqlReader("Password") And NET_ID.Text = sqlReader("NET_ID")) Then
                Response.Redirect("~/Request/Creation.aspx")
            End If
        End While
        sqlReader.Close()
        command.Dispose()
        connection.Close()
    Catch ex As Exception
        MsgBox(ex.Message)
    End Try

End Sub

谢谢大家

我无法使用VB.NET连接到我的SQL Server数据库

3 个答案: