WPF Listview Access to SelectedItem and subitems

问题

Ok, I am having more problems with my C# WPF ListView control. Here it is in all its glory:

<Window x:Class="ebook.SearchResults" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"Title="ISBNListView" Height="503" Width="1004">
<Grid>
    <ListView Name="listView1" Margin"22,30,33,28" MouseDoubleClick="getSelectedItem" >

        <ListView.View>
            <GridView>
                <GridView.Columns>
                    <GridViewColumn Header="ISBN" Width="150" DisplayMemberBinding="{Binding ISBN}"/>
                    <GridViewColumn Header="Title" Width="350" DisplayMemberBinding="{Binding Title}"/>
                    <GridViewColumn Header="Author" Width="350" DisplayMemberBinding="{Binding Author}" />
                </GridView.Columns>
            </GridView>
        </ListView.View>
    </ListView>
</Grid>

I am filling the listView with the following:

XDocument xdoc = XDocument.Load(GlobalVars.docPath + "\\tempSearchResults.xml");
        var items = from item in xdoc.Descendants("Book")
                    select new
                    {
                        ISBN = item.Element("ISBN").Value,
                        Title = item.Element("Title").Value,
                        AuthTexts = item.Element("Author").Value
                    };
        foreach (var item in items)
        {
            listView1.Items.Add(new { ISBN = item.ISBN, Title = item.Title, Author = item.AuthTexts });
        }

I am having a devil of a time retrieving data from a row when it is double clicked. The DoubleClick does popup a message box with all the data in the row, I just cannot seem to get only one subitem or cell's data. Say a row has ISBN: 1234567 Title: Hurrr Author: Waldo, how do I just retrieve the ISBN or just the title?

private void getSelectedItem(object sender, MouseButtonEventArgs e)
    {
        System.Windows.MessageBox.Show(listView1.SelectedItems[0].ToString());
    }

Still new to C# and .Net and banging my head against the wall. I figure this should be rather simple.

回答1:

listView1.SelectedItems[0] returns an object. You first need to cast it to its specific type before you can access its members. For casting you need to know the name of the class to cast to, but you're adding instances of an anonymous class (= has no name) to your ListView.

Solution: Define a class (e.g., Book) with ISBN, Title and Author properties and add instances of Book to the ListView. Then you can do the necessary cast:

private void getSelectedItem(object sender, MouseButtonEventArgs e)
{
    Book book = (Book)listView1.SelectedItems[0];
    System.Windows.MessageBox.Show(book.ISBN);
}

Don't forget to add instances if Book to the ListView instead of instances of an anonymous type:

var items = from item in xdoc.Descendants("Book")
            select new Book                                   //  <---
            {
                ISBN = (string)item.Element("ISBN"),
                Title = (string)item.Element("Title"),
                Author = (string)item.Element("Author"),
            };

foreach (var item in items)
{
    listView1.Items.Add(item);
}

回答2:

    var items = from item in xdoc.Descendants("Book")
            select new Book()                                   //  <---
            {
                ISBN = (string)item.Element("ISBN"),
                Title = (string)item.Element("Title"),
                Author = (string)item.Element("Author"),
            };

foreach (var item in items)
{
    listView1.Items.Add(item);
}

I have got an issue with code above, once I use it, my listView did not list any of those values. I do not know if that will help you or if that is correct but after a few tests I added () after "select new Book" and then ListView could show all fields correctly for me.

来源：https://stackoverflow.com/questions/1402878/wpf-listview-access-to-selecteditem-and-subitems

标签

wpf

listview

selecteditem