1、生成XML的例子
function TBSCWS.GetBUYDS(Search_Condition: string): String;
var ts:Tstringlist;
begin
ts:=Tstringlist.Create;
ts.Add ('<?xml version="1.0"?>');
ts.add('<!--购货数据-->');
ts.add('<BILLS>');
with dm1.INFOS_QUERYdo
begin
sql.Text :='select Bill_id,Coal_id,Vehicle_count,mark_weight,trim_weight,buy_date,rs_id,vehicle_number from tlb_buy '+Search_condition+' order by bill_ID';
open;
while not eofdo
begin
ts.add('<BILL BILL_ID="'+fieldbyname('bill_id').asstring+'">');
ts.add('<BUY_DATE>'+formatdatetime('yyyy-mm-dd',fieldbyname('BUY_DATE').AsDateTime) +'</BUY_DATE>');
ts.add('<RS_ID>'+fieldbyname('RS_ID').AsString +'</RS_ID>');
ts.add('<COAL_ID>'+fieldbyname('coal_id').AsString+'</COAL_ID>');
ts.add('<VEHICLE_COUNT>'+fieldbyname('vehicle_count').AsString +'</VEHICLE_COUNT>');
ts.add('<MARK_WEIGHT>'+fieldbyname('MARK_weight').AsString +'</MARK_WEIGHT>');
ts.add('<TRIM_WEIGHT>'+fieldbyname('trim_weight').AsString +'</TRIM_WEIGHT>');
ts.add('<PAL>'+currtostr(fieldbyname('trim_weight').AsCurrency-fieldbyname('MARK_weight').AsCurrency)+'</PAL>');
ts.add('<VEHICLE_NUMBER>'+fieldbyname('VEHICLE_NUMBER').AsString +'</VEHICLE_NUMBER>');
ts.add('</BILL>');
next
end;
close;
end;
ts.add('</BILLS>');
result:=xttocompressSoapPacket(ts.DelimitedText);
ts.Free;
end;
解释，根据表生成XML，需注意的是XML是大小写敏感的。
2、用到的函数库，我用的是李维那本SOAP书里带的库
unit uSoapPacketComUnCompressor;
interface
uses
SysUtils, Classes;
function XTToCompressSoapPacket(const spPacket: string): string;
function XTToUnCompressSoapPacket(const spPacket: string): string;
function XTCompressedSize(const spPacket: string): Integer;
implementation
uses Zlib, EncdDecd;
function XTToCompressSoapPacket(const spPacket: string): string;
var
msCompressed : TMemoryStream;
zlibCompressor : TCompressionStream;
ssData : TStringStream;
begin
msCompressed := TMemoryStream.Create;
ssData := TStringStream.create('');
try
zlibCompressor := TCompressionStream.Create(clDefault,
msCompressed);
zlibCompressor.Write(spPacket[1], length(spPacket));
finally
FreeAndNil(zlibCompressor);
end;
try
msCompressed.Position := 0;
EncodeStream(msCompressed, ssData);
Result := sSData.Datastring;
finally
FreeAndNil(msCompressed);
FreeAndNil(ssData);
end;
end;
function XTToUnCompressSoapPacket(const spPacket: string): string;
var
msData : TMemoryStream;
msEncoded : TMemoryStream;
zlibUnCompressor : TDeCompressionStream;
fBufLen : integer;
fBuffer : array[0..16383] of byte;
begin
msData := TMemoryStream.create;
msEncoded := TMemoryStream.create;
try
msData.size := length(spPacket);
move(spPacket[1], msData.memory^, msData.size);
msData.position := 0;
DecodeStream(msData, msEncoded);
msData.size := 0;
msEncoded.position := 0;
zlibUnCompressor := TDeCompressionStream.create(msEncoded);
try
fBufLen := zlibUnCompressor.Read(fBuffer, SizeOf(fBuffer));
while fBufLen > 0do
begin
msData.Write(fBuffer, fBufLen);
fBufLen := zlibUnCompressor.Read(fBuffer, SizeOf(fBuffer));
end;
finally
FreeAndNil(zlibUnCompressor);
end;
msData.position := 0;
SetLength(Result, msData.size);
move(msData.memory^, Result[1], msData.size);
finally
FreeAndnil(msEncoded);
FreeAndNil(msData);
end;
end;
function XTCompressedSize(const spPacket: string): Integer;
var
msCompressed : TMemoryStream;
zlibCompressor : TCompressionStream;
begin
msCompressed := TMemoryStream.Create;
try
zlibCompressor := TCompressionStream.Create(clDefault,
msCompressed);
zlibCompressor.Write(spPacket[1], length(spPacket));
finally
FreeAndNil(zlibCompressor);
end;
try
msCompressed.Position := 0;
Result := msCompressed.Size;
finally
FreeAndNil(msCompressed);
end;
end;
end.
3、客户端接收到数据后的处理
procedure TBuyListForm.Button1Click(Sender: TObject);
var
ts:Tstringlist;
s:string;
begin
screen.Cursor:=crhourglass;
try
clientdataset1.Close;
ts:=Tstringlist.Create;
s:=bsc.GetBUYDS(' where year(buy_date)='+inttostr(year)+' and '
+'month(buy_date)='+inttostr(month));
ts.DelimitedText:=AnsiToUtf8(xtTOUncompressSoapPacket(s));
ts.SaveToFile(extractfilepath(application.ExeName)+'temp/buytemp.xml');
XmlTp.XMLDataFile:=extractfilepath(application.ExeName)+'temp/buytemp.xml';
XmlTp.TransformRead.TransformationFile:=extractfilepath(application.ExeName)+'xml/buy_todp.xtr';
clientdataset1.Open;
label1.Caption :=inttostr(year)+'年'+inttostr(month)+'月'；
finally
ts.Free;
screen.Cursor :=crdefault;
end;
end;
解释
ts.DelimitedText:=AnsiToUtf8(xtTOUncompressSoapPacket(s));
将收到后的数据解压缩并UTF8编码。xtTOUncompressSoapPacket为解码并解压缩函数。
ts.SaveToFile(extractfilepath(application.ExeName)+'temp/buytemp.xml');
保存临时文件
XmlTp.XMLDataFile:=extractfilepath(application.ExeName)+'temp/buytemp.xml';
XmlTp.TransformRead.TransformationFile:=extractfilepath(application.ExeName)+'xml/buy_todp.xtr';
clientdataset1.Open;
根据临时文件解析XML到DATASET，这里你需要使用DELPHI带的XML MAPPER工具，生成一个TODP
的XMLTRANSFORMATIONFILE（就是如何把XML映射到数据集的文件）
这里的XMLTP是一个XML TRANSFORMPROVIDER控件，在DATA ACCESS面板上。CLIENTDATASET的
ProviderName就设为它。
bsc：是WEBSERVICE的接口
4、这个数据的流程为
数据库-->xml-->压缩并编码-->通过HTTP传递到客户-->解码并解压缩-->到临时文件-->通过 XmlTransformProvider解析并向clientDataset提供数据。
