BCB中xml做数据库的例子.rar_C Builder_C++builder _ListView_XML BCB_buil

//--------------------------------------------------------------------------- #include "my_xml.h" myXML::myXML():XmlDoc(NULL),Root(NULL),SavePause(0) { } //----------------------------------------------------------------------- myXML::myXML(AnsiString fpath) : XmlDoc(NULL),Root(NULL),SavePause(0) { init(fpath); } //----------------------------------------------------------------------- void myXML::init(AnsiString fpath) { _fpath = fpath; if( NULL != XmlDoc )delete XmlDoc; //我对这行代码没有信心，还请高人指点。 XmlDoc = NULL; if( fpath.Length() == 0 ) { } else { if(FileExists(fpath)) //如果文件存在 { try{ XmlDoc = LoadXMLDocument(fpath);} catch(...){ XmlDoc = NULL;} } else //如果文件不存在， { try{ XmlDoc = NewXMLDocument(L"1.0"); } //创建, L""表示宽字符串。 catch(...){ XmlDoc = NULL;} if( NULL == XmlDoc ){} else XmlDoc->FileName = fpath; } } if(XmlDoc == NULL){ Root = NULL; } else { XmlDoc->Encoding = AnsiString("UTF-16"); //编码方式还可以选择： //"gb2312" 与一般中文文本兼容 //"utf-8" 适于全部是英文的情况。 //"big5" 台湾繁体中文 Root = XmlDoc->DocumentElement; if( Root == NULL ) { XmlDoc->AddChild("root"); //根节点，必须有一个。一般用"root" Root = XmlDoc->DocumentElement; } } SavePause = 0; } //--------------------------------------------------------------------- bool myXML :: isNull()const{ return (Root == NULL); } //--------------------------------------------------------------------- void myXML :: save()const //存盘 { if( Root == NULL )return; if( SavePause > 0 )return; if( _fpath.Length() == 0 )return; if( XmlDoc->Modified ) { try{ XmlDoc->SaveToFile( _fpath ); }catch(...){} } } //--------------------------------------------------------------------- xmlNode myXML :: root()const{ return xmlNode(Root);} //--------------------------------------------------------------------- void myXML :: disable_save(){ ++SavePause; } //--------------------------------------------------------------------- void myXML :: enable_save(){ --SavePause; save(); } //--------------------------------------------------------------------- void myXML::save_to( AnsiString fpath_ )const //保存到... { if( Root == NULL )return; try{ XmlDoc->SaveToFile( fpath_ ); }catch(...){} } //--------------------------------------------------------------------- //=========================================================================== //--------------------------------------------------------------------- //本函数用于替换掉字符串中含有的非法字符，防止其写入xml文件中。 //这里简单的用空格替换，不一定合适。有待大家指正。 static AnsiString & Valid(AnsiString & str) { const int Len = str.Length(); for(int i=1;i<=Len;++i) { char & c = str[i]; if(c > 0x00 && c < 0x20)c = ' '; } return str; } //----------------------------------------------------------------------- xmlNode :: xmlNode(){ _node = NULL; } //----------------------------------------------------------------------- xmlNode :: xmlNode(_di_IXMLNode node){ _node = node;} //----------------------------------------------------------------------- void xmlNode :: init(_di_IXMLNode node){ _node = node;} //----------------------------------------------------------------------- bool xmlNode :: isNull()const{ return (_node == NULL); } //----------------------------------------------------------------------- xmlNode & xmlNode::operator = ( const xmlNode & node_ ) { _node = node_._node; return *this; } //----------------------------------------------------------------------- //返回一个名字是name的子节点，如果没有，创建一个。 xmlNode xmlNode :: get_child_node(AnsiString name)const { if(_node == NULL)return xmlNode(NULL); _di_IXMLNode node = _node->ChildNodes->FindNode(name); if(node == NULL) { return xmlNode(_node->AddChild(name)); } else return xmlNode(node); } //----------------------------------------------------------------------- //返回名字是name的子节点。 xmlNode xmlNode :: find_child_node(AnsiString name)const { if(_node == NULL)return xmlNode(NULL); return xmlNode(_node->ChildNodes->FindNode(name)); } //----------------------------------------------------------------------- AnsiString xmlNode :: name()const { if(_node == NULL)return AnsiString(); return _node->NodeName; } //----------------------------------------------------------------------- AnsiString xmlNode :: value()const //获得该节点的字符串值。 { if(_node == NULL)return AnsiString(); AnsiString S; try { OleVariant v = _node->Text; if(v.IsNull())S = AnsiString(); else S = AnsiString(v); } catch(...){ S = AnsiString();} return S; } //----------------------------------------------------------------------- AnsiString xmlNode :: child_value(AnsiString name)const //返回子节点的值。 { if(_node == NULL)return AnsiString(); AnsiString S; try { OleVariant v = _node->ChildValues[name]; if(v.IsNull())S = AnsiString(); else S = AnsiString(v); } catch(...){ S = AnsiString();} return S; } //----------------------------------------------------------------------- void xmlNode::set_value( AnsiString value_ )const { if(_node == NULL)return; Valid( value_ ); try{ _node->Text = value_; }catch(...){} } //----------------------------------------------------------------------- void xmlNode :: set_child_value(AnsiString name,AnsiString value)const { if(_node == NULL)return ; Valid(value); const _di_IXMLNode node = _node->ChildNodes->FindNode(name); if(node == NULL) { if(value.Length() == 0); else { try{ _node->AddChild(name)->Text = value;}catch(...){} } } else { if(value.Length() == 0) { try{ _node->ChildNodes->Remove(node);}catch(...){} } else { try{ _node->ChildValues[name] = value;}catch(...){} } } } //----------------------------------------------------------------------- AnsiString xmlNode :: attribute(AnsiString name)const { if(_node == NULL)return AnsiString(); AnsiString S; try{ OleVariant v = _node->Attributes[name]; if(v.IsNull())S = AnsiString(); else S = AnsiString(v); } catch(...){ S = AnsiString();} return S; } //----------------------------------------------------------------------- void xmlNode :: set_attribute(AnsiString name,AnsiString value)const { if(_node == NULL)return ; Valid(value); if(value.Length() == 0) { try{ _node->Attributes[name] = Null();}catch(...){} } else { try{ _node->Attributes[name] = value;}catch(...){} } } //----------------------------------------------------------------------- void xmlNode :: find_child_nodes(vector<xmlNode> & nodes)const { if(_node == NULL)return ; _di_IXMLNodeList List = _node->ChildNodes; for(int i=0;i<List->Count;i++) { if( List->Nodes[i]->NodeType == ntElement ) { nodes.push_back(List->Nodes[i]); } } } //----------------------------------------------------------------------- //一次获得本节点所有的属性。 void xmlNode :: get_attrs(map<AnsiString,AnsiString> & attrs)const { if(_node == NULL)return ; _di_IXMLNodeList List = _node->AttributeNodes ; for(int i=0;i<List->Count;i++) { AnsiStrin