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  1. PO
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    <p>Your code using ListView virtual mode still lack some of important information. Firstly, we need set value to <strong>VirtualListSize</strong> property of ListView. Secondly, we need setup a cache value to retrieve ListItem correctly.</p> <p>We should keep in mind the RetrieveVirtualItem event <strong>always required return a ListViewItem</strong>.</p> <p>You can reference at here: <a href="http://msdn.microsoft.com/en-us/library/system.windows.forms.listview.virtualmode%28v=vs.90%29.aspx" rel="nofollow">http://msdn.microsoft.com/en-us/library/system.windows.forms.listview.virtualmode%28v=vs.90%29.aspx</a></p> <p>I have modified your code base on my assume, you can modify it following your idea. Hope this help.</p> <pre><code>public partial class Form1 : Form { private ListViewItem[] myCache; //array to cache items for the virtual list private int firstItem; //stores the index of the first item in the cache public Form1() { InitializeComponent(); _fileInfoCollection = new Queue&lt;ListViewFileInfo&gt;(); } private void GetFileInformation(string drive) { _fileInfoCollection.Clear(); var directory = new DirectoryInfo(drive); var files = directory.GetFiles("*.*", SearchOption.TopDirectoryOnly); myCache = new ListViewItem[files.Length]; int temp = 0; foreach (var file in files) { _fileInfoCollection.Enqueue(new ListViewFileInfo() { FileName = file.Name, FilePath = file.FullName }); ListViewFileInfo fileInfo = _fileInfoCollection.Dequeue(); var listViewItem = new ListViewItem(); listViewItem.Text = fileInfo.FileName; var listViewSubItem = new ListViewItem.ListViewSubItem(); listViewSubItem.Text = fileInfo.FilePath; listViewItem.SubItems.Add(listViewSubItem); myCache[temp] = listViewItem; temp++; } listView1.VirtualListSize = myCache.Length; } private void listView1_RetrieveVirtualItem(object sender, RetrieveVirtualItemEventArgs e) { if (myCache != null &amp;&amp; e.ItemIndex &gt;= firstItem &amp;&amp; e.ItemIndex &lt; firstItem + myCache.Length) { //A cache hit, so get the ListViewItem from the cache instead of making a new one. e.Item = myCache[e.ItemIndex - firstItem]; } else { //A cache miss, so create a new ListViewItem and pass it back. e.Item = new ListViewItem(); } } private void comboBoxDrive_SelectedIndexChanged(object sender, EventArgs e) { GetFileInformation(comboBoxDrive.Text); } private Queue&lt;ListViewFileInfo&gt; _fileInfoCollection; } </code></pre>
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    1. POListView virtualization requires a valid ListViewItem to be provided by the RetrieveVirtualItem event or in the OnRetrieveVirtualItem method
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    1. USToan Vo
    1. USToan Vo
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    1. COHi.. I just used your code and it didn't throw any error but however the listview doesn't show any items. Is there anything else I need to correct ?
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      1. USSanz Bajracharya
    2. COI have made a test my code. At my side it working as expected. I believe problem is another place. You should make sure the comboDrive return has slash \ symbol at the end of drive character. One more important thing your code just only list out the file not directory. So if there is not any file the list will blank. Hope this help.
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      1. USToan Vo
    3. CONo, I have debug the code and the list has 213 files. But, I don't know why it is not filling that listview. I have try this with simple folder containing 213 files. Is there any other places where i need to correct it.
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      1. USSanz Bajracharya
 

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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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