Delphi读写UTF-8、Unicode格式文本文件
// UTF-8文件写入函数
procedure SaveUTFFile(const FileName: string; S: string; WriteHeader: Boolean = True);
var
MemStream: TMemoryStream;
HeaderStr: String;
begin
if S = '' then Exit;
MemStream := TMemoryStream.Create;
try
if WriteHeader then
begin
HeaderStr:=#$EF#$BB#$BF;
MemStream.Write(HeaderStr[1], 3);
end;
try
if WriteHeader then
begin
HeaderStr:=#$EF#$BB#$BF;
MemStream.Write(HeaderStr[1], 3);
end;
S := AnsiToUtf8(S);
MemStream.Write(S[1], Length(S));
MemStream.Position := 0;
MemStream.Write(S[1], Length(S));
MemStream.Position := 0;
MemStream.SaveToFile(FileName);
finally
MemStream.Free;
end;
end;
finally
MemStream.Free;
end;
end;
// UtF-8文件读取函数
function LoadUTFFile(const FileName: string; ReadHeader: Boolean = True): string;
var
MemStream: TMemoryStream;
S, HeaderStr:string;
begin
Result:='';
if not FileExists(FileName) then Exit;
MemStream := TMemoryStream.Create;
try
MemStream.LoadFromFile(FileName);
if ReadHeader then
begin
SetLength(HeaderStr, 3);
MemStream.Read(HeaderStr[1], 3);
try
MemStream.LoadFromFile(FileName);
if ReadHeader then
begin
SetLength(HeaderStr, 3);
MemStream.Read(HeaderStr[1], 3);
if HeaderStr = #$EF#$BB#$BF then
begin
SetLength(S, MemStream.Size - 3);
MemStream.Read(S[1], MemStream.Size - 3);
end;
end else
begin
SetLength(S, MemStream.Size);
MemStream.Read(S[1], MemStream.Size);
end;
Result := Utf8ToAnsi(S);
finally
MemStream.Free;
end;
end;
begin
SetLength(S, MemStream.Size - 3);
MemStream.Read(S[1], MemStream.Size - 3);
end;
end else
begin
SetLength(S, MemStream.Size);
MemStream.Read(S[1], MemStream.Size);
end;
Result := Utf8ToAnsi(S);
finally
MemStream.Free;
end;
end;
// Unicode文件写入函数
procedure SaveUnicodeFile(const FileName:string; const S: string; WriteHeader: Boolean = True);
var
MemStream: TMemoryStream;
HeaderStr: string;
WStr: WideString;
begin
if S = '' then exit;
MemStream := TMemoryStream.Create;
try
if WriteHeader then
begin
HeaderStr := #$FF#$FE;
MemStream.Write(HeaderStr[1], 2);
end;
WStr := WideString(S);
MemStream.Write(WStr[1], Length(WStr)*2);
MemStream.Position := 0;
MemStream.SaveToFile(FileName);
finally
MemStream.Free;
end;
end;
try
if WriteHeader then
begin
HeaderStr := #$FF#$FE;
MemStream.Write(HeaderStr[1], 2);
end;
WStr := WideString(S);
MemStream.Write(WStr[1], Length(WStr)*2);
MemStream.Position := 0;
MemStream.SaveToFile(FileName);
finally
MemStream.Free;
end;
end;
// Unicode文件读取函数
function LoadUnicodeFile(const FileName: string; ReadHeader: Boolean = True): string;
var
MemStream: TMemoryStream;
FlagStr: String;
WStr: WideString;
begin
Result := '';
if not FileExists(FileName) then Exit;
function LoadUnicodeFile(const FileName: string; ReadHeader: Boolean = True): string;
var
MemStream: TMemoryStream;
FlagStr: String;
WStr: WideString;
begin
Result := '';
if not FileExists(FileName) then Exit;
MemStream := TMemoryStream.Create;
try
MemStream.LoadFromFile(FileName);
try
MemStream.LoadFromFile(FileName);
if ReadHeader then
begin
SetLength(FlagStr, 2);
MemStream.Read(FlagStr[1], 2);
if FlagStr = #$FF#$FE then
begin
SetLength(WStr, (MemStream.Size-2) div 2);
MemStream.Read(WStr[1], MemStream.Size - 2);
end;
end else
begin
SetLength(WStr, MemStream.Size div 2);
MemStream.Read(WStr[1], MemStream.Size);
end;
Result := AnsiString(WStr);
finally
MemStream.Free;
end;
end;
begin
SetLength(FlagStr, 2);
MemStream.Read(FlagStr[1], 2);
if FlagStr = #$FF#$FE then
begin
SetLength(WStr, (MemStream.Size-2) div 2);
MemStream.Read(WStr[1], MemStream.Size - 2);
end;
end else
begin
SetLength(WStr, MemStream.Size div 2);
MemStream.Read(WStr[1], MemStream.Size);
end;
Result := AnsiString(WStr);
finally
MemStream.Free;
end;
end;
http://blog.csdn.net/missmecn/article/details/3007964