65
votes

I have just started using WPF forms instead of Windows Forms forms. In a Windows Forms form I could just do:

ComboBox.SelectedValue.toString();

And this would work fine.

How do I do this in WPF? It doesn't seem to have the option.

22
Try SelectedItem. And why are you using typename ComboBox as variable name?!The Smallest
I'm not actually using ComboBox as the variable name. I should have made it clearer the combo box is actually cboType so I am using cboType.SelectedValue.toString(). I have tried selectedItem but it doesn't just give me the value it also shows System.Windows.Controls.ComboBoxItem: Software. Software being the value name which I only want that value so the rest before hand. Thanks for your helpBoardy
I interpreted "WF" as meaning "Windows Forms", not "Windows Workflow Foundation". What is correct? (Respond by editing your question, not here in comments.)Peter Mortensen
@PeterMortensen I'm not sure what you're getting at, the question says WPF at every point, never WFBoardy

22 Answers

91
votes

I have figured it out a bit of a strange way of doing it compared to the old WF forms:

ComboBoxItem typeItem = (ComboBoxItem)cboType.SelectedItem;
string value = typeItem.Content.ToString();
85
votes

Well.. I found a simpler solution.

String s = comboBox1.Text;

This way I get the selected value as string.

12
votes

My XAML is as below:

<ComboBox Grid.Row="2" Grid.Column="1" Height="25" Width="200" SelectedIndex="0" Name="cmbDeviceDefinitionId">
    <ComboBoxItem Content="United States" Name="US"></ComboBoxItem>
    <ComboBoxItem Content="European Union" Name="EU"></ComboBoxItem>
    <ComboBoxItem Content="Asia Pacific" Name="AP"></ComboBoxItem>
</ComboBox>

The content is showing as text and the name of the WPF combobox. To get the name of the selected item, I have follow this line of code:

ComboBoxItem ComboItem = (ComboBoxItem)cmbDeviceDefinitionId.SelectedItem;
string name = ComboItem.Name;

To get the selected text of a WPF combobox:

string name = cmbDeviceDefinitionId.SelectionBoxItem.ToString();
10
votes

Ensure you have set the name for your ComboBox in your XAML file:

<ComboBox Height="23" Name="comboBox" />

In your code you can access selected item using SelectedItem property:

MessageBox.Show(comboBox.SelectedItem.ToString());
7
votes

It depends what you bound to your ComboBox. If you have bound an object called MyObject, and have, let's say, a property called Name do the following:

MyObject mo = myListBox.SelectedItem as MyObject;
return mo.Name;
7
votes

How about these:

string yourstringname = (yourComboBox.SelectedItem as ComboBoxItem).Content.ToString();
4
votes

As a variant in the ComboBox SelectionChanged event handler:

private void ComboBoxName_SelectionChanged(object send ...
{
    string s = ComboBoxName.Items.GetItemAt(ComboBoxName.SelectedIndex).ToString();
}
3
votes

I had a similar issue and tried a number of solutions suggested in this thread but found that the SelectionChanged Event was firing before the ComboBox item had actually updated to show the new selection (i.e. so it always gave the contents of the combobox prior to the change occurring).

In order to overcome this, I found that it was better to use the e parameter that is automatically passed to the event handler rather than trying to load the value directly from the combo box.

XAML:

<Window.Resources>
    <x:Array x:Key="Combo" Type="sys:String">
        <sys:String>Item 1</sys:String>
        <sys:String>Item 2</sys:String>
    </x:Array>
</Window.Resources>
<Grid>
    <ComboBox Name="myCombo" ItemsSource="{StaticResource Combo}" SelectionChanged="ComboBox_SelectionChanged" />
    <TextBlock Name="MyTextBlock"></TextBlock>
</Grid>

C#:

private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    string chosenValue = e.AddedItems[0].ToString();
}
3
votes

Solving this problem is simple. All I did was to add "SelectedValuePath" to my XAML code and bind it to my model property that I want to return with the combobox.

<ComboBox SelectedValuePath="_Department"
          DisplayMemberPath="_Department"
          Height="23"
          HorizontalAlignment="Left"
          ItemsSource="{Binding}"
          Margin="-58,1,0,5"
          Name="_DepartmentComboBox"
          VerticalAlignment="Center"
          Width="268"/>
2
votes

This largely depends on how the box is being filled. If it is done by attaching a DataTable (or other collection) to the ItemsSource, you may find attaching a SelectionChanged event handler to your box in the XAML and then using this in the code-behind useful:

private void ComboBoxName_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    ComboBox cbx = (ComboBox)sender;
    string s = ((DataRowView)cbx.Items.GetItemAt(cbx.SelectedIndex)).Row.ItemArray[0].ToString();
}

I saw 2 other answers on here that had different parts of that - one had ComboBoxName.Items.GetItemAt(ComboBoxName.SelectedIndex).ToString();, which looks similar but doesn't cast the box to a DataRowView, something I found I needed to do, and another: ((DataRowView)comboBox1.SelectedItem).Row.ItemArray[0].ToString();, used .SelectedItem instead of .Items.GetItemAt(comboBox1.SelectedIndex). That might've worked, but what I settled on was actually the combination of the two I wrote above, and don't remember why I avoided .SelectedItem except that it must not have worked for me in this scenario.

If you are filling the box dynamically, or with ComboBoxItem items in the dropdown directly in the XAML, this is the code I use:

private void ComboBoxName_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    ComboBox cbx = (ComboBox)sender;
    string val = String.Empty;
    if (cbx.SelectedValue == null)
        val = cbx.SelectionBoxItem.ToString();
    else
        val = cboParser(cbx.SelectedValue.ToString());
}

You'll see I have cboParser, there. This is because the output from SelectedValue looks like this: System.Windows.Controls.Control: Some Value. At least it did in my project. So you have to parse your Some Value out of that:

private static string cboParser(string controlString)
{
    if (controlString.Contains(':'))
    {
        controlString = controlString.Split(':')[1].TrimStart(' ');
    }
    return controlString;
}

But this is why there are so many answers on this page. It largely depends on how you are filling the box, as to how you can get the value back out of it. An answer might be right in one circumstance, and wrong in the other.

2
votes

Create a ComboBox SelectionChanged Event and set ItemsSource="{Binding}" in the WPF design:

Code:

private void comboBox1_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    string ob = ((DataRowView)comboBox1.SelectedItem).Row.ItemArray[0].ToString();
    MessageBox.Show(ob);
}
1
votes
private void usuarioBox_TextChanged(object sender, EventArgs e)
{
    string textComboBox = usuarioBox.Text;
}
0
votes
MsgBox(cmbCut.SelectedValue().ToString())
0
votes

To get the value of the ComboBox's selected index in C# use:

Combobox.SelectedValue
0
votes

It's the same principle.

You can either use SelectedIndex and use ComboBox.Items[SelectedIndex].ToString(). Or just ComboBox.SelectedItem and cast it to any type you need :)

0
votes

Actually you can do it the following way as well.

Suppose your ComboBox name is comboBoxA. Then its value can be gotten as:

string combo = comboBoxA.SelectedValue.ToString();

I think it's now supported since your question is five years old.

0
votes

Write it like this:

String CmbTitle = (cmb.SelectedItem as ComboBoxItem).Content.ToString()
0
votes

if you want to get the value and validate it you can do something like this

string index = ComboBoxDB.Text;
        if (index.Equals(""))
        {                
            MessageBox.Show("your message");
        }
        else
        {
            openFileDialog1.ShowDialog();
            string file = openFileDialog1.FileName;
            reader = new StreamReader(File.OpenRead(file));
        }
0
votes
        // -----------------------------------------------------------------

        private void onSelectionChanged(object sender, 
                                        SelectionChangedEventArgs e)
        {
            String result = ((ComboBox)sender).SelectedItem.ToString();
            // do something with result
        }

        // -----------------------------------------------------------------
-1
votes

I use this code, and it works for me:

DataRowView typeItem = (DataRowView)myComboBox.SelectedItem; 
string value = typeItem.Row[0].ToString();
-2
votes

XAML:

<ComboBox Height="23" HorizontalAlignment="Left" Margin="19,123,0,0" Name="comboBox1" VerticalAlignment="Top" Width="33" ItemsSource="{Binding}" AllowDrop="True" AlternationCount="1">
    <ComboBoxItem Content="1" Name="ComboBoxItem1" />
    <ComboBoxItem Content="2" Name="ComboBoxItem2" />
    <ComboBoxItem Content="3" Name="ComboBoxItem3" />
</ComboBox>

C#:

if (ComboBoxItem1.IsSelected)
{
    // Your code
}
else if (ComboBoxItem2.IsSelected)
{
    // Your code
}
else if(ComboBoxItem3.IsSelected)
{
    // Your code
}
-3
votes

It works for me:

System.Data.DataRowView typeItem = (System.Data.DataRowView)ComboBoxName.SelectedItem;
string value = typeItem.DataView.ToTable("a").Rows[0][0].ToString();