symbian 数据库字段长度

核心提示：TDbCol(const TDesC& aName,TDbColType aType);TDbCol(const TDesC& aName,TDbColType aType,TInt aMaxLength);EDbColText ： 默认长度 50， 自定义长度 aMaxLengthEDbColLongText ：基本

TDbCol(const TDesC& aName,TDbColType aType);

TDbCol(const TDesC& aName,TDbColType aType,TInt aMaxLength);

EDbColText ： 默认长度 50， 自定义长度 aMaxLength

EDbColLongText ：基本不限制长度，但需要用流读写，如：

void CDBColStream::WriteStream( RDbTable& atable, TDbColNo aCol, const TDesC& adescription )

{

RDbColWriteStream writeStream;

writeStream.OpenLC(atable,aCol);

writeStream.WriteL(adescription);

writeStream.Close();

CleanupStack::Pop();

}

void CDBColStream::ReadStream( RDbTable& atable, TDbColNo aCol, HBufC* description )

{

TInt length = atable.ColLength(aCol);

RDbColReadStream readStream;

readStream.OpenLC(atable,aCol);

TPtr16 temp(description->Des());

readStream.ReadL(temp,length);

readStream.Close();

CleanupStack::Pop(); //readStream

}