1、jQuery對象的構建從其原理可以看出，其統一的入口就是jQuery對象。那么這個對象是如何生成的呢？ jQuery的實質是Query，那么生成jQuery對象就可能看作是構建并運行一個查詢器。既然是查詢，肯定會有查找到的結果(Dom元素)，那么這些結果又存放在 哪里呢？最好的地方當然是jQuery對象內面。查詢的結果可能是單個元素，也可能是集合如NodeSet。也就是說jQuery對象內面應該有一個集合。且這個集合是用來存 放查詢到Dom元素。但jQuery對象是所有操作的統一入口，那么它的構建就不應只局限 于從Dom文檔樹中查詢到Dom元素，有可能是從別的集合中轉移過來的Dom 元素，或是

2、html的片斷生成的Dom元素。Jquery 文檔中提供 了 四種構建方式：jQuery(expression,context)， jQuery(html)，jQuery(elements)，jQuery(callback)。其中 jQuery 可以用$代替。這 四種方式是經常用到。其實Jquery的參數可以是任何的元素。也就是說任何的 參數都可以構建jquery對象。舉幾個例子：1、$($( “P”)可以看出其參數可以是jQuery對象或ArrayLike的集合。2、$()是$(document)的簡寫。3、$(3)會把3放到jQuery對象中集合中。對于如$(3)這樣的其中元素(如Arra

3、yLike集合的元素)不是Dom元素，最 好不要構建jQuery對象，jQuery對象的方法設計的目的都是針對于dom對象的 而進行的操作。如果不清楚其使用的話，很有可能會導致錯誤。上面講了這么多大道理，現在從源碼的角度細細分析：通過jQuery(xxx)的調用實現沒有生成對象，它的this是指向window對象的。那么jQuery的那些實例方法是怎樣繼承過來的呢？看一下：var jQuery = window.jQuery = window,$ =function(selector, context) (returnnew jQuery.fn.init(selector, context);

4、這是jquery的總入口，jQuery對象不是通過new jQuery來繼承其prototype中的方法，而是jQuery.fn.init函數生成的對象。這里我們可以看出對于jQtotype添加一些函數集的對象的意義不大。new jQuery()還是可以的，但是生成的jQuery對象在return時會被拋棄。故不要 用new jQuery()來構建jQuery對象。jQuery 對象其實就是 jQuery.fn.init 對象。那么 jQtotype 上就是掛著jQuery對象的操作方法。如jQtotype = jQuery.fn;有時間可能會擔心在589行就實現了把jQuery.fn中的函數

5、放到jQtotype上去， 那么之后的通過jquery.fn.extend的方法怎么辦呢？這里是對jQuery.fn的引用。在擴展jQuery的時候，只要把相關的函數extend到jQuery.fn 就可以了。現在我們看一下jQuery.fn.init是怎么完成工作的：init :function(selector, context) (selector = selector | document;/定 selector 存在/第一種情況Handle $(DOMElement)單個Dom元素，忽略上下文if (selector.nodeType) (this0 = selector;this.

6、length = 1;returnthis;if (typeof selector =string) (/selector 為 stringvar match = quickExpr.exec(selector);if (match & (match1 II !context)(if (match1)/第 二種情況處理 $(html) - $(array)selector = jQuery.clean(match1, context);else (/第三種情況：HANDLE: $(#id)/處理$(#id)var elem = document.getElementById(match3);i

7、f(elem) (/ IE會返回name=id的元素，如果是這樣，就document.find(s)if (elem.id != match3)return jQuery().find(selector);構建一個新的jQuery(elem)return jQuery(elem);selector =; else/第四種情況：處理 $(expr, context)=$(content).find(expr) TOC o 1-5 h z return jQuery(context).find(selector); elseif (jQuery.isFunction(selector)/第五種情況

8、：處理$(function)七 Shortcut for document readyreturn jQuery(document)jQuery.fn.ready ? ready : load(selector);/第六種情況：處理$(elements)returnthis.setArray(jQuery.makeArray(selector);,jQuery.fn.init負責對傳進來的參數進行分析然后生成jQuery對象。它的第一 個參數一般來說是必須的(為空的話，就是默認的document)。從源碼的角度第 一個參數有著如下四種類型：類型Dom /Element/String說明第一個參

9、數為Dom元素，第二個參數不用。直接把Dom元素存在新生成的jQuery對象的集合中。返回這個jQuery對象。構建jQuery對象完成。第一個參數為string有三種情況：1、html的標簽字符串，$(html) - $(array)，第二個參數可選。執行 selector = jQuery.clean(match1, context)。該語句是把hteml的字符串轉換成dom對象的數組。接著執行Array類 型的返回。2、字符串為#id時$(id)首先通過 var elem = document.getElementById(match3)取得elem，如沒有取到selector =;轉到

10、執行Array類型的返回 空集合jquery對象。如找到elem，通過return jQuery(elem);再次生成jquery對象， 這次是Dom Element類型的jquery對象的返回。3、兼容css1-3語法的selector字符串，第二個參數是可選的。執行 return jQuery(context).find(selector);。該語句先執行 jQuery(context)。可以看出context第二參數可以是任意的值， 可以是集合形式。之后就通過find(selector)找到 jQuery(context)中所有dom 元素都滿足selector表達式的dom 元素的集合

11、，構建新的jquery對象，并返回。#id其實和這種方式是統一的，單獨出來是 為了提高性能。C+ Source Part OnekhmanagerView.cpp : implementation of the CKhmanagerView class#include stdafx.h#include khmanager.h#include khmanagerDoc.h#include khmanagerView.h#ifdef _DEBUG#define new DEBUG_NEW#undef THIS_FILEstatic char THIS_FILE = _FILE_;#endifCKh

12、managerViewIMPLEMENT_DYNCREATE(CKhmanagerView, CView) BEGIN_MESSAGE_MAP(CKhmanagerView, CView) AFX_MSG_MAP(CKhmanagerView) AFX_MSG_MAPStandard printing commandsON_COMMAND(ID_FILE_PRINT, CView:OnFilePrint) ON_COMMAND(ID_FILE_PRINT_DIRECT, CView:OnFilePrint) ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView:OnF

13、ilePrintPreview) END_MESSAGE_MAP()CKhmanagerView constructiondestructionCKhmanagerView:CKhmanagerView()CKhmanagerView:CKhmanagerView()BOOL CKhmanagerView:PreCreateWindow(CREATESTRUCT& cs)return CView:PreCreateWindow(cs);CKhmanagerView drawingvoid CKhmanagerView:OnDraw(CDC pDC)CKhmanagerDoc pDoc = Ge

14、tDocument();ASSERT_VALID(pDoc);CKhmanagerView printingBOOL CKhmanagerView:OnPreparePrinting(CPrintInfo pInfo)default preparationreturn DoPreparePrinting(pInfo);void CKhmanagerView:OnBeginPrinting(CDC pDC, CPrintInfo pInfo)void CKhmanagerView:OnEndPrinting(CDC pDC, CPrintInfo pInfo)CKhmanagerView dia

15、gnostics#ifdef _DEBUGvoid CKhmanagerView:AssertValid() constCView:AssertValid();void CKhmanagerView:Dump(CDumpContext& dc) constCView:Dump(dc);CKhmanagerDoc CKhmanagerView:GetDocument() non-debug version is inlineASSERT(m_pDocument-IsKindOf(RUNTIME_CLASS(CKhmanagerDoc);return (CKhmanagerDoc)m_pDocum

16、ent;#endif _DEBUGCKhmanagerView message handlersC+ Source Part Two#if !defined(AFX_OFFICER_H_DD010A11_0E5B_4762_B002_A3488892C751_INCLUDED_)#define AFX_OFFICER_H_DD010A11_0E5B_4762_B002_A3488892C751_INCLUDED_#if _MSC_VER 1000#pragma once#endif _MSC_VER 1000OFFICER.h : header fileCOFFICER dialogclass

17、 COFFICER : public CDialogConstructionpublic:COFFICER(CWnd pParent = NULL); standard constructor圖像數據參數與方法HBITMAPm_hPhotoBitmap;DWORDm_nFileLen;HBITMAPBufferToHBITMAP();BOOLLoadBMPFile(const char pBMPPathname);charm_pBMPBuffer;voidDestroyPhoto();voidDrawUserPhoto(int x,int y,CDC pDC);CBrush m_brush_s

18、tatic;labelCBrush m_brush_dlg;dlgDialog DataAFX_DATA(COFFICER)enum IDD = IDD_OFFICRER_DLG ;CString m_stroffjzlx;CString m_stroffsex;CString m_stroffzc;CString m_stroffzw;CTime m_timeoffbirth;CString m_stroffid;CString m_stroffjiguan;CString m_stroffjzbh;CString m_strofflxdz;CString m_stroffminzu;CSt

19、ring m_stroffmark;CString m_stroffname;CString m_stroffphone;CString m_stroffpostcode;CString m_stroffzjh;CString m_stroffzsdz;AFX_DATAOverridesClassWizard generated virtual function overridesAFX_VIRTUAL(COFFICER)protected:virtual void DoDataExchange(CDataExchange pDX); DDXDDV support AFX_VIRTUALImp

20、lementationprotected:Generated message map functionsAFX_MSG(COFFICER)afx_msg void OnButtonZyTijiao();afx_msg void OnButtonJlLoadphoto();afx_msg void OnPaint();virtual BOOL OnInitDialog();afx_msg HBRUSH OnCtlColor(CDC pDC, CWnd pWnd, UINT nCtlColor);AFX_MSGDECLARE_MESSAGE_MAP();AFX_INSERT_LOCATIONMic

21、rosoft Visual C+ will insert additional declarations immediately before the previous line.#endif !defined(AFX_OFFICER_H_DD010A11_0E5B_4762_B002_A3488892C751_INCLUDED_)C+ Source Part Three#if !defined(AFX_DLGPURVIEW_H_9BCBBC19_B958_11D7_A240_5254AB3E4F7E_INCLUDED_)#defineAFX_DLGPURVIEW_H_9BCBBC19_B95

22、8_11D7_A240_5254AB3E4F7E_INCLUDED_#if _MSC_VER 1000#pragma once#endif _MSC_VER 1000DlgPurview.h : header file#include myfunction.hCDlgPurview dialogclass CDlgPurview : public CDialogConstructionpublic:CDlgPurview(CWnd pParent = NULL); standard constructorDialog DataAFX_DATA(CDlgPurview)enum IDD = ID

23、D_DIALOG_XIUGAI_PURVIEW ;CButton m_btnXitong;CButton m_btnJichuxinxi;CButton m_btnZhangmu;CButton m_btnCaiwu;CButton m_btnDiaohuo;CButton m_btnKucun;CButton m_btnRuku;CButton m_btnXiaoshou;int m_iPurview;BOOL m_bXiaoshou;BOOL m_bRuku;BOOL m_bKucun;BOOL m_bDiaohuo;BOOL m_bCaiwu;BOOL m_bZhangmu;BOOL m

24、_bJichuxinxi;BOOL m_bXitong;AFX_DATAint m_iOldPurview;int m_iNewPurview;LRunSql m_runsql;OverridesClassWizard generated virtual function overrides(AFX_VIRTUAL(CDlgPurview)protected:virtual void DoDataExchange(CDataExchange pDX); DDXDDV supportAFX_VIRTUALImplementationprotected:void ChangeData(int pu

25、rview,CString field,bool b_value);void GetDataFromDatabase(int purview);void RefreshData(int purview);Generated message map functionsAFX_MSG(CDlgPurview)virtual BOOL OnInitDialog();virtual void OnOK();afx_msg void OnRadio1();afx_msg void OnRadio2();afx_msg void OnRadio3();afx_msg void OnRadio4();afx

26、_msg void OnCheck2();afx_msg void OnCheck3();afx_msg void OnCheck5();afx_msg void OnCheck6();afx_msg void OnCheck7();afx_msg void OnCheck8();afx_msg void OnCheck9();afx_msg void OnCheck10();AFX_MSGDECLARE_MESSAGE_MAP();AFX_INSERT_LOCATIONMicrosoft Visual C+ will insert additional declarations immedi

27、ately before the previous line.#endif !defined(AFX_DLGPURVIEW_H_9BCBBC19_B958_11D7_A240_5254AB3E4F7E_ INCLUDED_)C+ Source Part Foural.cpp : Defines the class behaviors for the application.#include stdafx.h#include a1.h#include a1Dlg.h#include MyFrame.h#include ScrollPrintDoc.h#include ScrollPrintVie

28、w.h#include myfunction.h#include DlgLogin.h#ifdef _DEBUG#include TRACEWIN.H#endif#ifdef _DEBUG#define new DEBUG_NEW#undef THIS_FILEstatic char THIS_FILE = _FILE_;#endifCA1AppBEGIN_MESSAGE_MAP(CA1App, CWinApp)(AFX_MSG_MAP(CA1App)AFX_MSG_MAPON_COMMAND(ID_HELP, CWinApp:OnHelp)ON_COMMAND( ID_FILE_PRINT_

29、SETUP, OnFilePrintSetup ) END_MESSAGE_MAP()CA1App constructionCA1App:CA1App()TODO: add construction code here,Place all significant initialization in InitInstancethis-m_sUserName;this-m_sPurview=0;The one and only CA1App objectCA1App theApp;CA1App initializationBOOL CA1App:InitInstance()CG : Initial

30、ize OLE librariesif (!AfxOleInit()AfxMessageBox(_T(OLE initialization failed.); return FALSE;AfxEnableControlContainer();Standard initializationIf you are not using these features and wish to reduce the size of your final executable, you should remove from the following the specific initialization r

31、outines you do not need.#ifdef _AFXDLLEnable3dControls();Call this when using MFC in a shared DLL#elseEnable3dControlsStatic(); Call this when linking to MFC statically #endif#ifdef _DEBUGCMfxTrace:Init();#endifthis-SetRegistryKey(進銷存管理系統”)；WriteProfileInt(Settings”, x”, 23);WriteProfileInt(Settings

32、”, y”, 12);WriteProfileInt(Settings”, cx, 32);WriteProfileInt(Settings”, cy, 1233);WriteProfileInt(Settings, TraceWhere, 23);if(LRunSql:InitConnectPtr()=false) 初始化 COM 環境，進行數據庫連接 return false;pDocTemplate = new LSingleDocTemplate(IDR_MENU_MYFRAME,RUNTIME_CLASS(CScrollPrintDoc),RUNTIME_CLASS(CMyFrame

33、), main SDI frame window RUNTIME_CLASS(CScrollPrintView);AddDocTemplate(pDocTemplate);CMemoryState mem;mem.Checkpoint();CDlgLogin dlg;創建登錄窗口對象if(dlg.DoModal()=IDOK)顯示登錄窗口CAlDlg pdlg=new CAlDlg;創建主窗口對象 m_pMainWnd = pdlg;pdlg-DoModal(); 顯示主窗口delete pdlg;pdlg=NULL;mem.DumpAllObjectsSince();LRunSql:Clos

34、e();斷開數據庫連接Since the dialog has been closed, return FALSE so that we exit theapplication, rather than start the applications message pump.return FALSE;C+ Source Part FiveResetdatabase.cpp : implementation file#include stdafx.h#include Myhotel.h#include Resetdatabase.h#ifdef _DEBUG#define new DEBUG_N

35、EW#undef THIS_FILEstatic char THIS_FILE = _FILE_;#endifextern CMyhotelApp theApp;CResetdatabase dialogCResetdatabase:CResetdatabase(CWnd pParent =NULL):CDialog(CResetdatabase:IDD, pParent) (AFX_DATA_INIT(CResetdatabase)m_resetguazhang = FALSE;m_resetcheckoutreg = FALSE;m_resetcheckinreg = FALSE;m_re

36、setroombook = FALSE;m_resetroomstate = FALSE;AFX_DATA_INITvoid CResetdatabase:DoDataExchange(CDataExchange pDX)CDialog:DoDataExchange(pDX);AFX_DATA_MAP(CResetdatabase)DDX_Check(pDX, IDC_CHECKresetguazhang, m_resetguazhang);DDX_Check(pDX, IDC_CHECKresetcheckoutreg, m_resetcheckoutreg);DDX_Check(pDX,

37、IDC_CHECKresetcheckinreg, m_resetcheckinreg);DDX_Check(pDX, IDC_CHECKresetroombook, m_resetroombook);DDX_Check(pDX, IDC_CHECKresetroomstate, m_resetroomstate);AFX_DATA_MAPBEGIN_MESSAGE_MAP(CResetdatabase, CDialog)AFX_MSG_MAP(CResetdatabase)ON_BN_CLICKED(ID_beginresetdatabase, Onbeginresetdatabase)AF

38、X_MSG_MAPEND_MESSAGE_MAP()CResetdatabase message handlersvoid CResetdatabase:Onbeginresetdatabase()TODO: Add your control notification handler code here使輸入框可以接收輸入GetDlgItem(IDOK)-EnableWindow(1);GetDlgItem(IDC_groupdatabase)-EnableWindow(1);GetDlgItem(IDC_CHECKresetguazhang)-EnableWindow(1);GetDlgIt

39、em(IDC_CHECKresetcheckoutreg)-EnableWindow(1);GetDlgItem(IDC_CHECKresetcheckinreg)-EnableWindow(1);GetDlgItem(IDC_CHECKresetroombook)-EnableWindow(1);GetDlgItem(IDC_CHECKresetroomstate)-EnableWindow(1);BOOL CResetdatabase:OnInitDialog()CDialog:OnInitDialog();TODO: Add extra initialization here初始化各個輸

40、入框狀態GetDlgItem(IDOK)-EnableWindow(0);GetDlgItem(IDC_CHECKresetguazhang)-EnableWindow(0);GetDlgItem(IDC_CHECKresetcheckoutreg)-EnableWindow(0);GetDlgItem(IDC_CHECKresetcheckinreg)-EnableWindow(0);GetDlgItem(IDC_CHECKresetroombook)-EnableWindow(0);GetDlgItem(IDC_CHECKresetroomstate)-EnableWindow(0);Ge

41、tDlgItem(IDC_groupdatabase)-EnableWindow(0);return TRUE; return TRUE unless you set the focus to a controlEXCEPTION: OCX Property Pages should return FALSE void CResetdatabase:OnOK()TODO: Add extra validation here獲取輸入框內的數據UpdateData(true);m_pRecordset.CreateInstance(_uuidof(Recordset);if(m_resetroom

42、book)AfxMessageBox(wwwwww!);在ADO操作中建議語句中要常用try.catch()來捕獲錯誤信息，CString strsql;strsql.Format(DELETE FROM kfyd);try執行SQL語句，先打開數據表然后清空數據表m_pRecordset-Open(_variant_t)(strsql),查詢表中所有字段theApp.m_pConnection.GetInterfacePtr(),獲取庫接庫的IDispatch 指針adOpenDynamic, adLockOptimistic, adCmdText);MessageBox(成功初始化客房預定

43、登記表!”，”客房管理系統”)；catch(_com_error。)拋出異常情況，因該過程可能有異常出現AfxMessageBox(e-ErrorMessage();m_pRecordset-Close();m_pRecordset = NULL;m_pRecordsetin.CreateInstance(_uuidof(Recordset);if(m_resetcheckinreg)AfxMessageBox(wwwwww!);在ADO操作中建議語句中要常用try.catch()來捕獲錯誤信息，CString strsql;strsql.Format(DELETE FROM checkinr

44、egtable);try執行SQL語句，先打開數據表然后清空數據表m_pRecordsetin-Open(_variant_t)(strsql),查詢表中所有字段theApp.m_pConnection.GetInterfacePtr(), 獲取庫接庫的 IDispatch 指針adOpenDynamic, adLockOptimistic, adCmdText);MessageBox(成功初始化住宿登記表!”，”客房管理系統); catch(_com_error。)拋出異常情況，因該過程可能有異常出現 AfxMessageBox(e-ErrorMessage();m_pRecordset-Close();m_pRecordsetin = NULL;m_pRecordsetout.CreateInstance(_uuidof(Recordset);if(m_resetche