C# 在富文本框中的光标位置插入图像
我知道有很多这样的问题，但我问这些问题是因为我不明白所有的答案。我有C# 在富文本框中的光标位置插入图像,c#,winforms,image,richtextbox,C#,Winforms,Image,Richtextbox,我知道有很多这样的问题，但我问这些问题是因为我不明白所有的答案。我有RichTextBox，我希望用户能够在当前光标位置插入图像 我曾尝试使用剪贴板设置图像，然后将其粘贴到富文本框中。这是可行的，但有人告诉我它的坏习惯，因为它在没有通知用户的情况下更改剪贴板中的数据 这就是我尝试过的 private bool CheckIfImage(string filename) { if (filename.EndsWith(".jpeg")) { return true;
RichTextBox剪贴板设置图像，然后将其粘贴到富文本框中。这是可行的，但有人告诉我它的坏习惯，因为它在没有通知用户的情况下更改剪贴板中的数据
这就是我尝试过的
private bool CheckIfImage(string filename)
{
if (filename.EndsWith(".jpeg")) { return true; }
else if (filename.EndsWith(".jpg")) { return true; }
else if (filename.EndsWith(".png")) { return true; }
else if (filename.EndsWith(".ico")) { return true; }
else if (filename.EndsWith(".gif")) { return true; }
else if (filename.EndsWith(".bmp")) { return true; }
else if (filename.EndsWith(".emp")) { return true; }
else if (filename.EndsWith(".wmf")) { return true; }
else if (filename.EndsWith(".tiff")) { return true; }
else { return false; }
}
private void openFileDialog2_FileOk(object sender, CancelEventArgs e)
{
if (CheckIfImage(openFileDialog2.FileName.ToLower()) == true)
{
Image img = Image.FromFile(openFileDialog2.FileName);
string setData = (String)Clipboard.GetData(DataFormats.Rtf);
Clipboard.SetImage(img);
rtbType.Paste();
Clipboard.SetData(DataFormats.Rtf, setData);
}
else
{
MessageBox.Show("Invalid Image File Selected");
}
}
有没有更好的方法可以做到这一点？RichTextBox对OLE（对象链接和嵌入）的支持是一个历史性的意外。OLE是一种过时的技术，多年来一直受到严重的抨击。它的死亡丧钟肯定是.NET完全不支持它的。从本机RichEdit控件中删除OLE支持是明智的，但它会破坏太多古老的应用程序。.NET RichTextBox类本身只是本机组件的一个小包装器，不会从该组件中添加或删除功能
因此，在.NET中使用OLE api没有任何简单的方法。通过剪贴板进行复制/粘贴仍然有效，这只是一个意外，.NET与该操作无关，因此无法停止该操作
因此，是的，它仍然可以通过剪贴板工作，是使用该功能的唯一体面方式。当然还有更好的选择，像WebBrowser或Word interop这样的东西给了您更大的灵活性。PDF包装器很流行。WPF很好地支持复合文档。等等。您可以尝试使用WPF RichTextBox并将其托管在WinForms窗口中。使用WPF，您将能够非常轻松地在光标位置插入图像。我已经为您准备了一个使用RTF power发布的解决方案的完整功能示例
正如汉斯·帕桑（Hans Passant）所写：解决方案相当棘手，有一些有效的替代方案可以实现
顺便说一句，这是你的代码（重写）：
这是embedImage
方法：
private void embedImage(Image img)
{
var rtf = new StringBuilder();
// Append the RTF header
rtf.Append(@"{\rtf1\ansi\ansicpg1252\deff0\deflang1033");
// Create the font table using the RichTextBox's current font and append
// it to the RTF string
rtf.Append(GetFontTable(this.Font));
// Create the image control string and append it to the RTF string
rtf.Append(GetImagePrefix(img));
// Create the Windows Metafile and append its bytes in HEX format
rtf.Append(getRtfImage(img));
// Close the RTF image control string
rtf.Append(@"}");
richTextBox1.SelectedRtf = rtf.ToString();
}
以下是所有必要的方法：
private enum EmfToWmfBitsFlags
{
EmfToWmfBitsFlagsDefault = 0x00000000,
EmfToWmfBitsFlagsEmbedEmf = 0x00000001,
EmfToWmfBitsFlagsIncludePlaceable = 0x00000002,
EmfToWmfBitsFlagsNoXORClip = 0x00000004
};
private struct RtfFontFamilyDef
{
public const string Unknown = @"\fnil";
public const string Roman = @"\froman";
public const string Swiss = @"\fswiss";
public const string Modern = @"\fmodern";
public const string Script = @"\fscript";
public const string Decor = @"\fdecor";
public const string Technical = @"\ftech";
public const string BiDirect = @"\fbidi";
}
[DllImport("gdiplus.dll")]
private static extern uint GdipEmfToWmfBits(IntPtr _hEmf,
uint _bufferSize, byte[] _buffer,
int _mappingMode, EmfToWmfBitsFlags _flags);
private string GetFontTable(Font font)
{
var fontTable = new StringBuilder();
// Append table control string
fontTable.Append(@"{\fonttbl{\f0");
fontTable.Append(@"\");
var rtfFontFamily = new HybridDictionary();
rtfFontFamily.Add(FontFamily.GenericMonospace.Name, RtfFontFamilyDef.Modern);
rtfFontFamily.Add(FontFamily.GenericSansSerif, RtfFontFamilyDef.Swiss);
rtfFontFamily.Add(FontFamily.GenericSerif, RtfFontFamilyDef.Roman);
rtfFontFamily.Add("UNKNOWN", RtfFontFamilyDef.Unknown);
// If the font's family corresponds to an RTF family, append the
// RTF family name, else, append the RTF for unknown font family.
fontTable.Append(rtfFontFamily.Contains(font.FontFamily.Name) ? rtfFontFamily[font.FontFamily.Name] : rtfFontFamily["UNKNOWN"]);
// \fcharset specifies the character set of a font in the font table.
// 0 is for ANSI.
fontTable.Append(@"\fcharset0 ");
// Append the name of the font
fontTable.Append(font.Name);
// Close control string
fontTable.Append(@";}}");
return fontTable.ToString();
}
private string GetImagePrefix(Image _image)
{
float xDpi, yDpi;
var rtf = new StringBuilder();
using (Graphics graphics = CreateGraphics())
{
xDpi = graphics.DpiX;
yDpi = graphics.DpiY;
}
// Calculate the current width of the image in (0.01)mm
var picw = (int)Math.Round((_image.Width / xDpi) * 2540);
// Calculate the current height of the image in (0.01)mm
var pich = (int)Math.Round((_image.Height / yDpi) * 2540);
// Calculate the target width of the image in twips
var picwgoal = (int)Math.Round((_image.Width / xDpi) * 1440);
// Calculate the target height of the image in twips
var pichgoal = (int)Math.Round((_image.Height / yDpi) * 1440);
// Append values to RTF string
rtf.Append(@"{\pict\wmetafile8");
rtf.Append(@"\picw");
rtf.Append(picw);
rtf.Append(@"\pich");
rtf.Append(pich);
rtf.Append(@"\picwgoal");
rtf.Append(picwgoal);
rtf.Append(@"\pichgoal");
rtf.Append(pichgoal);
rtf.Append(" ");
return rtf.ToString();
}
private string getRtfImage(Image image)
{
// Used to store the enhanced metafile
MemoryStream stream = null;
// Used to create the metafile and draw the image
Graphics graphics = null;
// The enhanced metafile
Metafile metaFile = null;
try
{
var rtf = new StringBuilder();
stream = new MemoryStream();
// Get a graphics context from the RichTextBox
using (graphics = CreateGraphics())
{
// Get the device context from the graphics context
IntPtr hdc = graphics.GetHdc();
// Create a new Enhanced Metafile from the device context
metaFile = new Metafile(stream, hdc);
// Release the device context
graphics.ReleaseHdc(hdc);
}
// Get a graphics context from the Enhanced Metafile
using (graphics = Graphics.FromImage(metaFile))
{
// Draw the image on the Enhanced Metafile
graphics.DrawImage(image, new Rectangle(0, 0, image.Width, image.Height));
}
// Get the handle of the Enhanced Metafile
IntPtr hEmf = metaFile.GetHenhmetafile();
// A call to EmfToWmfBits with a null buffer return the size of the
// buffer need to store the WMF bits. Use this to get the buffer
// size.
uint bufferSize = GdipEmfToWmfBits(hEmf, 0, null, 8, EmfToWmfBitsFlags.EmfToWmfBitsFlagsDefault);
// Create an array to hold the bits
var buffer = new byte[bufferSize];
// A call to EmfToWmfBits with a valid buffer copies the bits into the
// buffer an returns the number of bits in the WMF.
uint _convertedSize = GdipEmfToWmfBits(hEmf, bufferSize, buffer, 8, EmfToWmfBitsFlags.EmfToWmfBitsFlagsDefault);
// Append the bits to the RTF string
foreach (byte t in buffer)
{
rtf.Append(String.Format("{0:X2}", t));
}
return rtf.ToString();
}
finally
{
if (graphics != null)
graphics.Dispose();
if (metaFile != null)
metaFile.Dispose();
if (stream != null)
stream.Close();
}
}
我建议您将其包装到您自己的UserControl
可能的副本：@DmitryBychenko该链接用于vb.net
…因此，基本上，他应该创建自己的文本框（或RichTextBox）包装器。@Precious1tj实际上您想要的东西可以解决，但它相当复杂，这是供您进一步研究的链接这几乎是我的答案，但当我这样添加图像时，图像边缘的质量似乎有所下降。不知道你是否能说出为什么会发生这种情况。我发现，如果我使用bmp instread png，我可以获得更好的质量
private enum EmfToWmfBitsFlags
{
EmfToWmfBitsFlagsDefault = 0x00000000,
EmfToWmfBitsFlagsEmbedEmf = 0x00000001,
EmfToWmfBitsFlagsIncludePlaceable = 0x00000002,
EmfToWmfBitsFlagsNoXORClip = 0x00000004
};
private struct RtfFontFamilyDef
{
public const string Unknown = @"\fnil";
public const string Roman = @"\froman";
public const string Swiss = @"\fswiss";
public const string Modern = @"\fmodern";
public const string Script = @"\fscript";
public const string Decor = @"\fdecor";
public const string Technical = @"\ftech";
public const string BiDirect = @"\fbidi";
}
[DllImport("gdiplus.dll")]
private static extern uint GdipEmfToWmfBits(IntPtr _hEmf,
uint _bufferSize, byte[] _buffer,
int _mappingMode, EmfToWmfBitsFlags _flags);
private string GetFontTable(Font font)
{
var fontTable = new StringBuilder();
// Append table control string
fontTable.Append(@"{\fonttbl{\f0");
fontTable.Append(@"\");
var rtfFontFamily = new HybridDictionary();
rtfFontFamily.Add(FontFamily.GenericMonospace.Name, RtfFontFamilyDef.Modern);
rtfFontFamily.Add(FontFamily.GenericSansSerif, RtfFontFamilyDef.Swiss);
rtfFontFamily.Add(FontFamily.GenericSerif, RtfFontFamilyDef.Roman);
rtfFontFamily.Add("UNKNOWN", RtfFontFamilyDef.Unknown);
// If the font's family corresponds to an RTF family, append the
// RTF family name, else, append the RTF for unknown font family.
fontTable.Append(rtfFontFamily.Contains(font.FontFamily.Name) ? rtfFontFamily[font.FontFamily.Name] : rtfFontFamily["UNKNOWN"]);
// \fcharset specifies the character set of a font in the font table.
// 0 is for ANSI.
fontTable.Append(@"\fcharset0 ");
// Append the name of the font
fontTable.Append(font.Name);
// Close control string
fontTable.Append(@";}}");
return fontTable.ToString();
}
private string GetImagePrefix(Image _image)
{
float xDpi, yDpi;
var rtf = new StringBuilder();
using (Graphics graphics = CreateGraphics())
{
xDpi = graphics.DpiX;
yDpi = graphics.DpiY;
}
// Calculate the current width of the image in (0.01)mm
var picw = (int)Math.Round((_image.Width / xDpi) * 2540);
// Calculate the current height of the image in (0.01)mm
var pich = (int)Math.Round((_image.Height / yDpi) * 2540);
// Calculate the target width of the image in twips
var picwgoal = (int)Math.Round((_image.Width / xDpi) * 1440);
// Calculate the target height of the image in twips
var pichgoal = (int)Math.Round((_image.Height / yDpi) * 1440);
// Append values to RTF string
rtf.Append(@"{\pict\wmetafile8");
rtf.Append(@"\picw");
rtf.Append(picw);
rtf.Append(@"\pich");
rtf.Append(pich);
rtf.Append(@"\picwgoal");
rtf.Append(picwgoal);
rtf.Append(@"\pichgoal");
rtf.Append(pichgoal);
rtf.Append(" ");
return rtf.ToString();
}
private string getRtfImage(Image image)
{
// Used to store the enhanced metafile
MemoryStream stream = null;
// Used to create the metafile and draw the image
Graphics graphics = null;
// The enhanced metafile
Metafile metaFile = null;
try
{
var rtf = new StringBuilder();
stream = new MemoryStream();
// Get a graphics context from the RichTextBox
using (graphics = CreateGraphics())
{
// Get the device context from the graphics context
IntPtr hdc = graphics.GetHdc();
// Create a new Enhanced Metafile from the device context
metaFile = new Metafile(stream, hdc);
// Release the device context
graphics.ReleaseHdc(hdc);
}
// Get a graphics context from the Enhanced Metafile
using (graphics = Graphics.FromImage(metaFile))
{
// Draw the image on the Enhanced Metafile
graphics.DrawImage(image, new Rectangle(0, 0, image.Width, image.Height));
}
// Get the handle of the Enhanced Metafile
IntPtr hEmf = metaFile.GetHenhmetafile();
// A call to EmfToWmfBits with a null buffer return the size of the
// buffer need to store the WMF bits. Use this to get the buffer
// size.
uint bufferSize = GdipEmfToWmfBits(hEmf, 0, null, 8, EmfToWmfBitsFlags.EmfToWmfBitsFlagsDefault);
// Create an array to hold the bits
var buffer = new byte[bufferSize];
// A call to EmfToWmfBits with a valid buffer copies the bits into the
// buffer an returns the number of bits in the WMF.
uint _convertedSize = GdipEmfToWmfBits(hEmf, bufferSize, buffer, 8, EmfToWmfBitsFlags.EmfToWmfBitsFlagsDefault);
// Append the bits to the RTF string
foreach (byte t in buffer)
{
rtf.Append(String.Format("{0:X2}", t));
}
return rtf.ToString();
}
finally
{
if (graphics != null)
graphics.Dispose();
if (metaFile != null)
metaFile.Dispose();
if (stream != null)
stream.Close();
}
}