vb.net组合框中公共重载子菜单参数太多

Question

vb.net组合框中公共重载子菜单参数太多vb.net组合框中的函数错误

Public Function combo(strQuery As String) As List(Of ComboBox)
Dim objlist As New List(Of ComboBox)
con.Open()
Dim dt As New DataTable
For Each dr In ExecuteReader(strQuery).Rows
objlist.Add(New ComboBox(Convert.ToInt32(dr.Item(0).ToString()), dr.Item(1).ToString()))
Next
con.Close()
Return objlist
End Function
<Extension>
Public Function ExecuteReader(strQuery As String) As DataTable
Dim dt As New DataTable
If con.State = ConnectionState.Open Then con.Close()
con.Open()
cmd = New SqlCommand(strQuery, con)
da = New SqlDataAdapter(cmd)
da.Fill(dt)
con.Close()
Return dt
End Function

Answer 1

ComboBox构造函数不接受任何参数。https://learn.microsoft.com/en - us/dotnet/api/system.windows.forms.combobox. ctor?view=windowsdesktop - 6.0

我认为你的函数应该是

Private Class ComboBoxItem
Public Property Id As Integer
Public Property Text As String
Public Sub New(Id As Integer, Text As String)
Me.Id = Id
Me.Text = Text
End Sub
End Class
Public Function GetPopulatedCombo(strQuery As String) As ComboBox
Dim Combo As ComboBox = New ComboBox
Combo.DisplayMember = "Text"
Using DT = ExecuteReader(strQuery)    
For Each dr In DT.Rows
Combo.Items.Add(New ComboBoxItem(dr.Item(0),dr.Item(1))
Next
End Using
Return Combo 
End Function