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BCB实现BLOB字段的读写2010-03-18对于SQL中的TEXT、IMAGE、MEMO字段的存取,可以采用下列程序:BLOB字段的读取:TBlobSTream* TemplateStream;
char* TempPlatePtr;
TemplateStream=new TBlobStream((TBlobField*)WebQuery->FieldByName
("SearchTem"),bmReadWrite);
TemplatePtr= new char[TemplateStream->Size];
TemplateStream->Read(TemplatePtr, TemplateStream->Size);
BLOB字段的写入:
TBlobSTream* TemplateStream;
char* TempPlatePtr;
TemplateStream=new TBlobStream((TBlobField*)WebQuery->FieldByName
("SearchTem"),bmReadWrite);
TemplatePtr= new char[TemplateStream->Size];
TemplateStream->Write(TemplatePtr, TemplateStream->Size);
________________________________________________________________补充:获得字段的大小用函数datalengthSQL Server端要作一点设置:By default, WRITETEXT is a nonlogged operation. This means thattext or image data is not logged when it is written into the database.To use WRITETEXT in its default, nonlogged state,//注意!!the system administrator must use the sp_dboption system storedprocedure to set select into/bulkcopy,//which allows nonlogged data to be inserted.做了试验,直接写SQL语句好象不行.____________________________________________________________________