Question

我试图将一些文本从网页拖放到Winform上的文本框中。所有这些都可以从MS Edge，Firefox Opera和Chrome中获得，但不是IE11或Safari。我在DragOver事件中使用的简短代码是：

 private void textBox1_DragDrop(object sender, DragEventArgs e)
 {
        if(e.Data.GetDataPresent(DataFormats.Text, false))
        {
            textBox1.Text = (string)e.Data.GetData(DataFormats.Text);
        }
 }

似乎IE和Safari的DataFormat不是Text，但我无法弄清楚它是什么。

当然，浏览器可能不会让我拖出文本。

任何想法导致我的问题？

谢谢，

学家

Answer 1

这是一种通过拖放操作获取所有可用格式数据的方法浏览器源工作正常（我测试了Edge，IE 11和FireFox）
源格式通常作为字符串或MemoryStream传递您可以根据自己的情况进一步调整。

<强>更新
重建主类对象。它现在更紧凑，处理更多细节。另外，我添加了一个样本VS样本WinForms表单来测试其结果。这是一个可以包含在VS项目中的标准表格。

Google云端硬盘：Drag & Drop sample Form

using System.Drawing;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Text.RegularExpressions;


private FileDropResults DD_Results;

public class FileDropResults
{
    public enum DataFormat : int
    {
        MemoryStream = 0,
        Text,
        UnicodeText,
        Html,
        Bitmap,
        ImageBits,
    }

    public FileDropResults() { this.Contents = new List<DropContent>(); }

    public List<DropContent> Contents { get; set; }

    public class DropContent
    {
        public object Content { get; set; }
        public string Result { get; set; }
        public DataFormat Format { get; set; }
        public string DataFormatName { get; set; }
        public List<Bitmap> Images { get; set; }
        public List<string> HttpSourceImages { get; set; }
    }
}

private void TextBox1_DragDrop(object sender, DragEventArgs e)
{
    GetDataFormats(e.Data);
}

private void TextBox1_DragEnter(object sender, DragEventArgs e)
{
    e.Effect = DragDropEffects.Copy;
}

private void GetDataFormats(IDataObject Data)
{
    DD_Results = new FileDropResults();
    List<string> _formats = Data.GetFormats(false).ToList<string>();

    foreach (string _format in _formats)
    {
        FileDropResults.DropContent CurrentContents = new FileDropResults.DropContent() 
        { DataFormatName = _format };

        switch (_format)
        {
            case ("FileGroupDescriptor"):
            case ("FileGroupDescriptorW"):
            case ("DragContext"):
            case ("UntrustedDragDrop"):
                break;
            case ("DragImageBits"):
                CurrentContents.Content = (MemoryStream)Data.GetData(_format, true);
                CurrentContents.Format = FileDropResults.DataFormat.ImageBits;
                break;
            case ("FileDrop"):
                CurrentContents.Content = null;
                CurrentContents.Format = FileDropResults.DataFormat.Bitmap;
                CurrentContents.Images = new List<Bitmap>();
                CurrentContents.Images.AddRange(
                    ((string[])Data.GetData(DataFormats.FileDrop, true))
                    .ToList()
                    .Select(img => Bitmap.FromFile(img))
                    .Cast<Bitmap>().ToArray());
                break;
            case ("HTML Format"):
                CurrentContents.Format = FileDropResults.DataFormat.Html;
                CurrentContents.Content = Data.GetData(DataFormats.Html, true);
                int HtmlContentInit = CurrentContents.Content.ToString().IndexOf("<html>", StringComparison.InvariantCultureIgnoreCase);
                if (HtmlContentInit > 0)
                    CurrentContents.Content = CurrentContents.Content.ToString().Substring(HtmlContentInit);
                CurrentContents.HttpSourceImages = DD_GetHtmlImages(CurrentContents.Content.ToString());
                break;
            case ("UnicodeText"):
                CurrentContents.Format = FileDropResults.DataFormat.UnicodeText;
                CurrentContents.Content = Data.GetData(DataFormats.UnicodeText, true);
                break;
            case ("Text"):
                CurrentContents.Format = FileDropResults.DataFormat.Text;
                CurrentContents.Content = Data.GetData(DataFormats.Text, true);
                break;
            default:
                CurrentContents.Format = FileDropResults.DataFormat.MemoryStream;
                CurrentContents.Content = Data.GetData(_format, true);
                break;
        }

        if (CurrentContents.Content != null)
        {
            if (CurrentContents.Content.GetType() == typeof(MemoryStream))
            {
                using (MemoryStream _memStream = new MemoryStream())
                {
                    ((MemoryStream)CurrentContents.Content).CopyTo(_memStream);
                    _memStream.Position = 0;

                    CurrentContents.Result = Encoding.Unicode.GetString(_memStream.ToArray());
                }
            }
            else
            {
                if (CurrentContents.Content.GetType() == typeof(String))
                    CurrentContents.Result = CurrentContents.Content.ToString();
            }
        }
        DD_Results.Contents.Add(CurrentContents);
    }
}

public List<string> DD_GetHtmlImages(string HtmlSource)
{
    MatchCollection matches = Regex.Matches(HtmlSource, @"<img[^>]+src=""([^""]*)""",
                              RegexOptions.CultureInvariant | RegexOptions.IgnoreCase);
    return (matches.Count > 0)
            ? matches.Cast<Match>()
                    .Select(x => x.Groups[1]
                    .ToString()).ToList()
            : null;
}

DragDrop文本从浏览器到TextBox

1 个答案: