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How to make Drag&Drop work?

I have a textbox on a winform in Visual Studio. I want to drag&drop files on it. This is what I have done:
public LangMerge()
{ InitializeComponent();
this.AllowDrop = true;
tbxFilepath.AllowDrop = true;
tbxFilepath.DragDrop += new DragEventHandler(tbxFilepath_DragDrop);
tbxFilepath.DragEnter += new DragEventHandler(tbxFilepath_DragEnter);
}
void tbxFilepath_DragDrop(object sender, DragEventArgs e)
{
string[] files = (string[])e.Data.GetData(DataFormats.FileDrop);
foreach (string file in files) tbxFilepath.Text=(file);
}
void tbxFilepath_DragEnter(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.FileDrop)) e.Effect = DragDropEffects.Copy;
}
Neither the drag effect nor the receiving of the file does not work. No error messages or warnings. What could be the problem?
UPDATE: I inserted breakpoints into the event handler methods and the code doesn't get into them in the first place, no matter what I do with the cursor.

You have set AllowDrop=true; and handled DragDrop() and DragEnter() events, however for winforms application you need to also handle TextBox.DragOver() event :
Something like this :
private void textBoxFile_DragOver(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.FileDrop))
e.Effect = DragDropEffects.Copy;
else
e.Effect = DragDropEffects.None;
}

Drag and Drop only PDF files

I have the following code that list the files that i drag in a listbox.
now i need to filter so it can only list PDF files and discard the rest.
private void Form1_Load(object sender, EventArgs e)
{
listBoxFiles.AllowDrop = true;
listBoxFiles.DragDrop += listBoxFiles_DragDrop;
listBoxFiles.DragEnter += listBoxFiles_DragEnter;
}
private void listBoxFiles_DragEnter(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.FileDrop))
e.Effect = DragDropEffects.Copy;
}
private void listBoxFiles_DragDrop(object sender, DragEventArgs e)
{
string[] files = (string[])e.Data.GetData(DataFormats.FileDrop);
foreach (string file in files)
listBoxFiles.Items.Add(file);
}

Try this:
private void listBoxFiles_DragDrop(object sender, DragEventArgs e)
{
string[] files = (string[])e.Data.GetData(DataFormats.FileDrop);
foreach (string file in files)
{
if (Path.GetExtension(file) == "pdf")
{
listBoxFiles.Items.Add(file);
}
}
}
Also, if it works - you can make it in one line with Linq

How to view selected item in listbox in image viewer asp.net

I have this code that populates my listbox that contains what I type in the textbox. My problem is how can I view the selected item in my listbox in a image viewer since all my files are images? Am I missing something?
Here's my code:
protected void Button1_Click(object sender, EventArgs e)
{
ListBox1.Items.Clear();
string[] files = Directory.GetFiles(Server.MapPath("~/images"), "*.*", SearchOption.AllDirectories);
foreach (string item in files)
{
string fileName = Path.GetFileName(item);
if (fileName.ToLower().Contains(TextBox1.Text.ToLower()))
{
ListBox1.Items.Add(fileName);
}
}
}
protected void ListBox1_SelectedIndexChanged(object sender, EventArgs e)
{
DocumentImage.ImageUrl = Directory.GetDirectories("~/images") + ListBox1.SelectedItem.ToString();
}

This should work I think:
protected void Button1_Click(object sender, EventArgs e)
{
ListBox1.Items.Clear();
string[] files = Directory.GetFiles(Server.MapPath("~/images"), "*.*", SearchOption.AllDirectories);
foreach (string item in files)
{
string fileName = Path.GetFileName(item);
if (fileName.ToLower().Contains(TextBox1.Text.ToLower()))
{
string subPath = item.Substring(Server.MapPath("~/images").Length).Replace("\\","/");
ListBox1.Items.Add(new ListItem(fileName, subPath));
}
}
}
In this part, you need to not only have the file name, but also the path where the file was found. In my sample, the sub path where the file was found is first set into subPath and that is then stored as the value for the list item.
protected void ListBox1_SelectedIndexChanged(object sender, EventArgs e)
{
DocumentImage.ImageUrl = "~/images" + ListBox1.SelectedItem.Value;
}
Here we use the sub path to set the correct url to the image.
Note that you need to have the AutoPostBack set to true on the DocumentImage in your asxp page in order for the image to change when you change the selection in the list box.

How can I drag a folder from my Windows Explorer into a ListView and load the files into it?

I can't seem to make this work using this:
private void listView1_DragEnter(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.FileDrop))
{
e.Effect = DragDropEffects.Copy;
}
}
private void listView1_DragDrop(object sender, DragEventArgs e)
{
string[] directoryName = (string[])e.Data.GetData(DataFormats.FileDrop);
string[] files = Directory.GetFiles(directoryName[0]);
foreach (string file in files)
{
if (Path.GetExtension(file) == ".mp3")
{
listView1.Items.Add(file);
}
}
}
The mouse cursor shows a NOT sign and I can't drop the folder in my program.

Have you set the AllowDrop property of your ListView to True?
Is your DragEnter event ever being hit?

drag files or folders in textbox? C#

How do i drag files or folders into a textbox? i want to put the foldername in that very textbox. C# .NET

i wrote this code based in this link
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
textBox1.AllowDrop = true;
textBox1.DragEnter += new DragEventHandler(textBox1_DragEnter);
textBox1.DragDrop += new DragEventHandler(textBox1_DragDrop);
}
private void textBox1_DragEnter(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.FileDrop))
e.Effects = DragDropEffects.Copy;
else
e.Effects = DragDropEffects.None;
}
private void textBox1_DragDrop(object sender, DragEventArgs e)
{
string[] FileList = (string[])e.Data.GetData(DataFormats.FileDrop, false);
string s="";
foreach (string File in FileList)
s = s+ " "+ File ;
textBox1.Text = s;
}
}

Set AllowDrop to true on your TextBox, and write the following code for the DragDrop and DragEnter events :
private void textBox1_DragEnter(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.FileDrop))
{
e.Effect = DragDropEffects.Copy;
}
}
private void textBox1_DragDrop(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.FileDrop))
{
string[] fileNames = (string[])e.Data.GetData(DataFormats.FileDrop);
textBox1.Lines = fileNames;
}
}

CodeProject has a really nice example of doing this, including how to enable drag and drop both ways (from Explorer to your app, and from your app to Explorer).

Control has various events for dealing with drag/drop - you'll probably only need to look at the DragDrop event for what you want.

If you get the Error Messages below, This applied to me when using Visual Studio 2015, try
e.Effect instead of e.Effects
Severity Code Description Project File Line Suppression State
Error CS1061 'DragEventArgs' does not contain a definition for 'Effects' and no extension method 'Effects' accepting a first argument of type 'DragEventArgs' could be found (are you missing a using directive or an assembly reference?)