拖动文件到窗体上，并显示文件路径

private void Form1_DragEnter(object sender, DragEventArgs e)
{
    if (e.Data.GetDataPresent(DataFormats.FileDrop)) e.Effect = DragDropEffects.Link;
    else e.Effect = DragDropEffects.None;
}


private void Form1_DragDrop(object sender, DragEventArgs e)
{
    string[] filePath = (string[])e.Data.GetData(DataFormats.FileDrop);


    this.textBox1.Text = filePath[0];
}