提问的智慧

[zrs413128313]

三层结构做通讯录,用vb.net编程,为什么不能修改记录.但是能增加和删除记录,调试时没有出错.本人怀疑是+[friend].ID.ToString 出错,因为他的返回值是0.望高手们回答为盼.
业务层代码如下:
Public Sub updatefriendbyid(ByVal [friend] As ContactEntry)

Dim conn As New SqlConnection
conn.ConnectionString = ConfigurationSettings.AppSettings("connectionstring")
Dim cmd As New SqlCommand
cmd.CommandText = "update contact set cname='" + [friend].cname + "',caddress='" + [friend].caddress + "',cemail='" + [friend].cphone + "',cphone='" + [friend].cemail + "',qq='" + [friend].qq + "'" + "where id= " +[friend].ID.ToString cmd.Connection = conn
conn.Open()
cmd.ExecuteNonQuery()
conn.Close()

End Sub

表现层的代码如下:
Private Sub btn1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn1.Click
If Page.IsValid Then
Dim [friend] As New ContactEntry
[friend].cname = txtname.Text
[friend].caddress = txtaddress.Text
[friend].cphone = txtphone.Text
[friend].cemail = txtemail.Text
[friend].qq = txtqq.Text
Dim contact As New contactDB
contact.updatefriendbyid([friend])
Response.Redirect("Default.aspx")
End If
End Sub

[wuyi8808]

提问的智慧?

三层结构做通讯录,用vb.net编程,为什么不能修改记录.但是能增加和删除记录,调试时没有出错.本人怀疑是+[friend].ID.ToString 出错,因为他的返回值是0.望高手们回答为盼.
业务层代码如下:

Public Sub updatefriendbyid(ByVal [friend] As ContactEntry) 

            Dim conn As New SqlConnection 
            conn.ConnectionString = ConfigurationSettings.AppSettings("connectionstring") 
            Dim cmd As New SqlCommand 
            cmd.CommandText = "update contact set cname='" + [friend].cname + "',caddress='" + [friend].caddress + "',cemail='" + [friend].cphone + "',cphone='" + [friend].cemail + "',qq='" + [friend].qq + "'" + "where id= " +[friend].ID.ToString          cmd.Connection = conn 
            conn.Open() 
            cmd.ExecuteNonQuery() 
            conn.Close() 

        End Sub 

表现层的代码如下:

Private Sub btn1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn1.Click 
        If Page.IsValid Then 
            Dim [friend] As New ContactEntry 
            [friend].cname = txtname.Text 
            [friend].caddress = txtaddress.Text 
            [friend].cphone = txtphone.Text 
            [friend].cemail = txtemail.Text 
            [friend].qq = txtqq.Text 
            Dim contact As New contactDB 
            contact.updatefriendbyid([friend]) 
            Response.Redirect("Default.aspx") 
        End If 
    End Sub

[wuyi8808]

[friend].ID.ToString()

[wuyi8808]

你数据库中的 id 字段是数值型的吗？
建议改成 string.Format() 的形式，这样清晰多了：

cmd.CommandText = string.Format("update contact set cname='{0}',caddress='{1}',cemail='{2}',cphone='{3}',qq='{4}' where id={5}", [friend].cname, [friend].caddress, [friend].cphone, [friend].cemail, [friend].qq, [friend].ID)

[zrs413128313]

还是不行,各位专家,请留下你们的QQ号吧,我想亲自问你们,我的QQ号是413128313

[wuyi8808]

你先在查询分析器中执行一下看。

[zrs413128313]

在查询分析器中是可以更新的,但在vb.net中就不行了