How to adding checked item from checkedlistbox to

问题:

I want to adding checked item from checkedlistbox to my combobox, but i have a little problem here. Combobox only show 1 item last checked. This is my sample code.

    If CheckedListBox1.CheckedItems.Count <> 0 Then
        For i As Integer = 0 To CheckedListBox1.CheckedItems.Count - 1
            cbCheckedItem.Text = CheckedListBox1.CheckedItems(i).ToString
        Next i
    End If

anyone can help me show all checked item?? thank's for your help...

回答1:

Oddly enough the CheckedListBox has a CheckedItems property, which is a collection. As such you can loop through it like you can any other collection, using a For or For Each loop.

then, Each item needs to be added to the Items collection of the ComboBox.

like this sample:

Public Class frmCheckedListBox

Private Sub frmCheckedListBox_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Me.CheckedListBox1.Items.Clear()
    Me.CheckedListBox1.BeginUpdate()
    Me.CheckedListBox1.Items.Add("One")
    Me.CheckedListBox1.Items.Add("Two")
    Me.CheckedListBox1.Items.Add("Three")
    Me.CheckedListBox1.Items.Add("Four")
    Me.CheckedListBox1.Items.Add("Five")
    Me.CheckedListBox1.EndUpdate()
End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    For Each Item As String In Me.CheckedListBox1.CheckedItems
        Me.ComboBox1.Items.Add(Item)
        Me.ComboBox1.SelectedIndex = 0
    Next
End Sub

End Class

As sample code shows, the CheckedItems collection contains the items that are checked, just as the name suggests. It doesn't contain a Boolean value for each an every item to indicate whether it is checked or not. If an item is checked then that item is in the CheckedItems, and if it isn't then it isn't. You simply need to loop through the collection and get every item in it, because it contains all the items that are checked and none that aren't.

in the end you can put :

Me.Combobox1.items.clear()

because when it would click with sample code it would have the one that clicked then on the next click would return the previous one it had clicked and then the new one all compiled in the combobox selection menu

perhaps my answer can help you solve your problems

回答2:

You aren't adding the items to the combo box, you're only setting its Text property. That's only changing the text currently displayed in the combo box, and only one item can be displayed at a time.

If you want the items to be permanent and selectable, you need to add them to the combo box control's Items collection.

Sample code:

If CheckedListBox1.CheckedItems.Count > 0 Then
    For Each checkedItem In CheckedListBox1.CheckedItems
        cbCheckedItem.Items.Add(checkedItem.ToString())
    Next
End If

Or, better yet, use the AddRange method:

If CheckedListBox1.CheckedItems.Count > 0 Then
    Dim checkedItems() As String = CheckedListBox1.CheckedItems.Cast(Of String).ToArray()
    cbCheckedItems.Items.AddRange(checkedItems)
End If

回答3:

Combobox doesn't have a multiselect option. so only one item at a time could be selected.