| File: System\Windows\Controls\DataGridClipboardHelper.cs | Web Access |
| Project: src\wpf\src\Microsoft.DotNet.Wpf\src\PresentationFramework\PresentationFramework.csproj (PresentationFramework) |
// Licensed to the .NET Foundation under one or more agreements. // The .NET Foundation licenses this file to you under the MIT license. using System.Globalization; using System.IO; using System.Text; using MS.Internal.Text; namespace System.Windows.Controls { internal static class DataGridClipboardHelper { internal static void FormatCell(object cellValue, bool firstCell, bool lastCell, StringBuilder sb, string format) { bool csv = string.Equals(format, DataFormats.CommaSeparatedValue, StringComparison.OrdinalIgnoreCase); if (csv || string.Equals(format, DataFormats.Text, StringComparison.OrdinalIgnoreCase) || string.Equals(format, DataFormats.UnicodeText, StringComparison.OrdinalIgnoreCase)) { if (cellValue != null) { bool escapeApplied = false; int length = sb.Length; FormatPlainText(cellValue.ToString(), csv, new StringWriter(sb, CultureInfo.CurrentCulture), ref escapeApplied); if (escapeApplied) { sb.Insert(length, '"'); } } if (lastCell) { // Last cell sb.Append('\r'); sb.Append('\n'); } else { sb.Append(csv ? ',' : '\t'); } } else if (string.Equals(format, DataFormats.Html, StringComparison.OrdinalIgnoreCase)) { if (firstCell) { // First cell - append start of row sb.Append("<TR>"); } sb.Append("<TD>"); // Start cell if (cellValue != null) { FormatPlainTextAsHtml(cellValue.ToString(), new StringWriter(sb, CultureInfo.CurrentCulture)); } else { sb.Append(" "); } sb.Append("</TD>"); // End cell if (lastCell) { // Last cell - append end of row sb.Append("</TR>"); } } } internal static void GetClipboardContentForHtml(StringBuilder content) { const int bytecountPrefixContext = 135; // Byte count of context before the content in the HTML format const int bytecountSuffixContext = 36; // Byte count of context after the content in the HTML format content.Insert(0, "<TABLE>"); content.Append("</TABLE>"); // The character set supported by the clipboard is Unicode in its UTF-8 encoding. // There are characters in Asian languages which require more than 2 bytes for encoding into UTF-8 // Marshal.SystemDefaultCharSize is 2 and would not be appropriate in all cases. We have to explicitly calculate the number of bytes. byte[] sourceBytes = Encoding.Unicode.GetBytes(content.ToString()); byte[] destinationBytes = InternalEncoding.Convert(Encoding.Unicode, Encoding.UTF8, sourceBytes); int bytecountEndOfFragment = bytecountPrefixContext + destinationBytes.Length; int bytecountEndOfHtml = bytecountEndOfFragment + bytecountSuffixContext; string prefix = string.Create(CultureInfo.InvariantCulture, $""" Version:1.0 StartHTML:00000097 EndHTML:{bytecountEndOfHtml:00000000} StartFragment:00000133 EndFragment:{bytecountEndOfFragment:00000000} <HTML> <BODY> <!--StartFragment--> """); content.Insert(0, prefix); content.Append( """ <!--EndFragment--> </BODY> </HTML> """); } private static void FormatPlainText(string s, bool csv, TextWriter output, ref bool escapeApplied) { if (s != null) { int length = s.Length; for (int i = 0; i < length; i++) { char ch = s[i]; switch (ch) { case '\t': if (!csv) { output.Write(' '); } else { output.Write('\t'); } break; case '"': if (csv) { output.Write("\"\""); escapeApplied = true; } else { output.Write('"'); } break; case ',': if (csv) { escapeApplied = true; } output.Write(','); break; default: output.Write(ch); break; } } if (escapeApplied) { output.Write('"'); } } } // Code taken from ASP.NET file xsp\System\Web\httpserverutility.cs; same in DataGridViewCell.cs private static void FormatPlainTextAsHtml(string s, TextWriter output) { if (s == null) { return; } int cb = s.Length; char prevCh = '\0'; for (int i = 0; i < cb; i++) { char ch = s[i]; switch (ch) { case '<': output.Write("<"); break; case '>': output.Write(">"); break; case '"': output.Write("""); break; case '&': output.Write("&"); break; case ' ': if (prevCh == ' ') { output.Write(" "); } else { output.Write(ch); } break; case '\r': // Ignore \r, only handle \n break; case '\n': output.Write("<br>"); break; // REVIEW: what to do with tabs? See original code in xsp\System\Web\httpserverutility.cs default: // The seemingly arbitrary 160 comes from RFC if (ch >= 160 && ch < 256) { output.Write("&#"); output.Write(((int)ch).ToString(NumberFormatInfo.InvariantInfo)); output.Write(';'); } else { output.Write(ch); } break; } prevCh = ch; } } } }