将 RTF 文本从数据库加载到 TRichEdit

发布于 2024-09-30 09:01:19 字数 556 浏览 1 评论 0原文

我目前正在将我们的软件解决方案从 Delphi 7 迁移到 2010。大部分更改都很简单，只剩下少量障碍。

在表单上，我们使用 TRichEdit，它显示从 MSSQL 数据库中的 blob 字段抓取的 rtf 文本。这就是它在 Delphi 7 中的工作方式：

//Get RTF text from Blob field using TADOQuery
rtfStream := sql.CreateBlobStream(sql.FieldByName('rtftext'), BmRead) as TMemoryStream;

//Load into TRichEdit
RichEdit.PlainText := False;
RichEdit.Lines.LoadFromStream(rtfStream);

这将按照 TRichEdit 组件中的预期显示 RTF，但 Delphi 2010 中的相同代码将 RTF 显示为纯文本，每个字符之间带有制表符。我认为这与从 Ansi 到 Unicode 的更改有很大关系，但我没有运气纠正这个问题。

任何帮助使其发挥作用将不胜感激。谢谢

原文

I am currently in the process of migrating our software solution from Delphi 7 to 2010. Mostly the changes have been simple and there are only a small amount of hurdles left to go.

On a form we use a TRichEdit which displayed rtf text grabbed from a blob field in a MSSQL db. This is how it worked in Delphi 7:

//Get RTF text from Blob field using TADOQuery
rtfStream := sql.CreateBlobStream(sql.FieldByName('rtftext'), BmRead) as TMemoryStream;

//Load into TRichEdit
RichEdit.PlainText := False;
RichEdit.Lines.LoadFromStream(rtfStream);

This would display the RTF as expected in the TRichEdit component, but the same code in Delphi 2010 displays the RTF as plain text with tabs between each character. I assume this has a lot to do with the change from Ansi to Unicode, but I haven't had any luck rectifying the problem.

Any help getting this to work would be much appreciated. Thanks

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━╋う一瞬間旳綻放 2024-10-07 09:01:19

好吧，我想通了。

用于加载 rtf 文本：

//Get the data from the database as AnsiString
rtfString := sql.FieldByName('rtftext').AsAnsiString;

//Write the string into a stream
stream := TMemoryStream.Create;
stream.Clear;
stream.Write(PAnsiChar(rtfString)^, Length(rtfString));
stream.Position := 0;

//Load the stream into the RichEdit
RichEdit.PlainText := False;
RichEdit.Lines.LoadFromStream(stream);

stream.Free;

用于保存 rtf 文本：

//Save to stream
stream := TMemoryStream.Create;
stream.Clear;

RichEdit.Lines.SaveToStream(stream);
stream.Position := 0;

//Read from the stream into an AnsiString (rtfString)
if (stream.Size > 0) then begin
    SetLength(rtfString, stream.Size);
    if (stream.Read(rtfString[1], stream.Size) <= 0) then
        raise EStreamError.CreateFmt('End of stream reached with %d bytes left to read.', [stream.Size]);
end;

stream.Free;

//Save to database
sql.FieldByName('rtftext').AsAnsiString := rtfString;

这花了我太长时间才弄清楚:)我想我已经学到了一件事......如果有的话Delphi 2010 中出错，通常与 unicode 有关；）

Okay I figured it out.

For loading the rtf text:

//Get the data from the database as AnsiString
rtfString := sql.FieldByName('rtftext').AsAnsiString;

//Write the string into a stream
stream := TMemoryStream.Create;
stream.Clear;
stream.Write(PAnsiChar(rtfString)^, Length(rtfString));
stream.Position := 0;

//Load the stream into the RichEdit
RichEdit.PlainText := False;
RichEdit.Lines.LoadFromStream(stream);

stream.Free;

For saving the rtf text:

//Save to stream
stream := TMemoryStream.Create;
stream.Clear;

RichEdit.Lines.SaveToStream(stream);
stream.Position := 0;

//Read from the stream into an AnsiString (rtfString)
if (stream.Size > 0) then begin
    SetLength(rtfString, stream.Size);
    if (stream.Read(rtfString[1], stream.Size) <= 0) then
        raise EStreamError.CreateFmt('End of stream reached with %d bytes left to read.', [stream.Size]);
end;

stream.Free;

//Save to database
sql.FieldByName('rtftext').AsAnsiString := rtfString;

This took me way too long to figure out :) I guess I have learned one thing though... if something goes wrong in Delphi 2010, its usually related to unicode ;)

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英雄似剑 2024-10-07 09:01:19

当 PlainText 为 False 时，LoadFromStream() 首先尝试加载 RTF 代码，如果失败，则 LoadFromStream() 尝试再次以纯文本形式加载流。所有 Delphi 版本都是如此。随着 Unicode 的引入，我认为 LoadFromStream() 的 EM_STREAMIN 回调处理程序中可能会出现某些问题。我建议您使用调试器进入 LoadFromStream() 的实际源代码，看看到底发生了什么。

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