c# - ASP.Net 表单抛出 SQL 异常

Question

当尝试在本地 SQL 数据库中保存和存储数据时，抛出 SQL 异常，

"A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)"

最初我认为我建立新数据连接的方式有问题。创建新表3次后，问题依旧。然后我尝试重新安装 Visual Studio 的 SQL 模块，它们也没有产生 +ve 结果。

无法从表中读取/存储任何数据。请帮忙。

public partial class signup : System.Web.UI.Page
{
    SqlConnection conn = new SqlConnection("Data Source=(localdb)\v11.0;Initial Catalog=KidzQuiz;Integrated Security=True");
    SqlCommand cmd;
    SqlDataAdapter da;
    DataSet ds;


protected void signupClick(object s, EventArgs e)
{
    //if (checkDuplicate() != 0)
        //signup_error.Text = "User already exists";
    //else if (checkEmpty() != 1)
       // signup_error.Text = "One or more fields is missing";
    //else
    //{
        string sqlcmd = "insert into User (name, email, school, city, standard, section) values (@n, @em, @sc, @city, @st, @sec)";
        cmd = new SqlCommand(sqlcmd, conn);
        cmd.Parameters.AddWithValue("@n", name.Text);
        cmd.Parameters.AddWithValue("@em", email_signup.Text);
        cmd.Parameters.AddWithValue("@sc", school.Text);
        cmd.Parameters.AddWithValue("@city", city.Text);
        cmd.Parameters.AddWithValue("@st", standard.SelectedItem.ToString());
        cmd.Parameters.AddWithValue("@sec", section.SelectedItem.ToString());
        conn.Open();
        cmd.ExecuteNonQuery();
        conn.Close();
    //}
}

Answer 1

在 LocalDB 本地数据库中，您还必须提供数据库文件的路径。

Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\db.mdf;Integrated Security=True

|数据目录|代表应用程序的App_Data文件夹