嘗試插入數據時ConfigurationManager出錯

Question

所以我試圖將數據添加到MySQL服務器數據庫。

下面是代碼：

Imports System.Data 
Imports System.Data.SqlClient 

Partial Class _Default 
    Inherits System.Web.UI.Page 

    Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click 
     Dim conn As String = ConfigurationManager.ConnectionStrings("Data Source=JOAOCOQUIM\SQLEXPRESS;Initial Catalog=Teste;Integrated Security=True").ConnectionString 
     Dim connection As SqlConnection = New SqlConnection(conn) 
     Dim sql As String = "Insert into [User] ([nome], [idade]) values (@nome, @idade)" 
     Dim cmd As SqlCommand = New SqlCommand(sql, connection) 
     cmd.Parameters.AddWithValue("@nome", TextBox1.Text) 
     cmd.Parameters.AddWithValue("@idade", TextBox2.Text) 


     connection.Open() 
     cmd.ExecuteNonQuery() 
     connection.Close() 
    End Sub 
End Class` 

當我插入數據，然後單擊Button顯示它的我下面的錯誤：

Answer 1

所以，我沒有說什麼錯誤，它工作。

這裏的工作代碼：

Imports System.Data 
Imports System.Data.SqlClient 

Partial Class _Default 
    Inherits System.Web.UI.Page 

    Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click 
     Dim conn As SqlConnection = New SqlConnection("Data Source=JOAOCOQUIM\SQLEXPRESS;Initial Catalog=Teste;Integrated Security=True") 
     Dim connection As SqlConnection = New SqlConnection("Data Source=JOAOCOQUIM\SQLEXPRESS;Initial Catalog=Teste;Integrated Security=True") 
     Dim sql As String = "Insert into [User] ([nome], [idade]) values (@nome, @idade)" 
     Dim cmd As SqlCommand = New SqlCommand(sql, connection) 
     cmd.Parameters.AddWithValue("@nome", TextBox1.Text) 
     cmd.Parameters.AddWithValue("@idade", TextBox2.Text) 


     connection.Open() 
     cmd.ExecuteNonQuery() 
     connection.Close() 
    End Sub 
End Class