`
BlogDown
  • 浏览: 223990 次
  • 性别: Icon_minigender_1
  • 来自: 上海
文章分类
社区版块
存档分类
最新评论

markup.h + markup.cpp

 
阅读更多

markup.h and markup.cpp in the http://www.firstobject.com/are the tools for the xml operatin in c++ language.

markup.h

markup.cpp

This article has been re-written with the help of 2 years of feedback, and the new source code has benefited from all of the fixes and developments during that time period. See release notes below.

Introduction

Often times you don't want to invest in learning a complex XML tool to implement a little bit of XML processing in your application. Its SO Easy! Just add Markup.cpp and Markup.h to your Visual C++ MFC project, #include "Markup.h", and begin using it. There are no other dependencies.

Features

  • Light: one small class that maintains one single document string with a simple array of indexes
  • Fast: the parser builds the index array in one quick pass
  • Simple: EDOM methods make it ridiculously easy to create or process XML strings
  • Independent: compiles into your program without requiring MSXML or any tokenizer
  • UNICODE: can be compiled for UNICODE for Windows CE and NT/XP platforms (define _UNICODE)
  • UTF-8: when not in UNICODE or MBCS builds, it works with UTF-8, ASCII, or Windows extended sets
  • MBCS: can be compiled for Windows double-byte character sets such as Chinese GB2312 (define _MBCS)

XML for Everyday Data

We often need to store and/or pass information in a file, or send a block of information from computer A to computer B. And the issue is always the same: How shall I format this data? Before XML, you might have considered "env" style e.g. PATH=C:/WIN95; "ini" style (grouped in sections); comma-delimited or otherwise delimited; or fixed character lengths. XML is now the established answer to that question except that programmers are sometimes discouraged by the size and complexity of XML solutions when all they need is something convenient to help parse and format angle brackets. For good minimalist reading on the syntax rules for XML tags, I recommend Beginning XML - Chapter 2: Well-Formed XML posted here on the Code Project.

XML is better because of its flexible and hierarchical nature, plus its wide acceptance. Although XML uses more characters than delimited formats, it compresses down well if needed. The flexibility of XML becomes apparent when you want to expand the types of information your document can contain without requiring every consumer of the information to rewrite processing logic. You can keep the old information identified and ordered the same way it was while adding new attributes and elements.

CMarkup Lite Methods

CMarkup is based on the "Encapsulated" Document Object Model (EDOM), the key to simple XML processing. Its a set of methods for XML processing with the same general purpose as DOM (Document Object Model). But while DOM has numerous types of objects, EDOM defines only one object, the XML document. EDOM harks back to the original attraction of XML which was its simplicity. To keep overhead low, CMarkup takes a very light non-conforming non-validating approach to XML, and it does not verify the XML is well-formed.

The CMarkup "Lite" in this article is the free version of the CMarkup product sold at firstobject.com. CMarkup Lite implements a subset of EDOM methods for creating and parsing XML document strings. The Lite methods also encompass some modification functionality such as setting an attribute or adding additional elements to an existing XML document, but not changing the data of, or removing, XML elements. See the EDOM specification to compare the full CMarkup with CMarkup Lite. The full CMarkup is available in Evaluation (Educational) and licensed Developer versions with many more methods, STL and MSXML versions, Base64, and additional documentation. But this Lite version here at Code Project is more than adequate for parsing and creating simple XML strings in MFC.

The CMarkup Lite methods are grouped into Creation and Navigation categories listed below.

CMarkup Lite Creation Methods

Collapse Copy Code 
CString GetDoc() const { return m_csDoc; };
bool AddElem( LPCTSTR szName, LPCTSTR szData=NULL );
bool AddChildElem( LPCTSTR szName, LPCTSTR szData=NULL );
bool AddAttrib( LPCTSTR szAttrib, LPCTSTR szValue );
bool AddChildAttrib( LPCTSTR szAttrib, LPCTSTR szValue );
bool SetAttrib( LPCTSTR szAttrib, LPCTSTR szValue );
bool SetChildAttrib( LPCTSTR szAttrib, LPCTSTR szValue );

GetDoc is used to get the document string after adding elements and setting attributes. The AddAttrib and SetAttrib methods do the same thing as each other (as do AddChildAttrib and SetChildAttrib). They will change the attribute's value if it already exists, and add the attribute if it doesn't.

CMarkup Lite Navigation Methods

Collapse Copy Code 
bool SetDoc( LPCTSTR szDoc );
bool IsWellFormed();
bool FindElem( LPCTSTR szName=NULL );
bool FindChildElem( LPCTSTR szName=NULL );
bool IntoElem();
bool OutOfElem();
void ResetChildPos();
void ResetMainPos();
void ResetPos();
CString GetTagName() const;
CString GetChildTagName() const;
CString GetData() const;
CString GetChildData() const;
CString GetAttrib( LPCTSTR szAttrib ) const;
CString GetChildAttrib( LPCTSTR szAttrib ) const;
CString GetError() const;

When you call SetDoc it parses the szDoc string and populates the CMarkup object. If it fails, it returns false, and you can call GetError for an error description. The IsWellFormed method returns true if the CMarkup object has at least a root element; it does not verify well-formedness.

Using CMarkup

The CMarkup class encapsulates the XML document text, structure, and current positions. It has methods both to add elements and to navigate and get element attributes and data. The locations in the document where operations are performed are governed by the current position and the current child position. This current positioning allows you to work with the XML document without instantiating additional objects that point into the document. At all times, the object maintains a string representing the text of the document which can be retrieved using GetDoc.

Check out the free firstobject XML editor which generates C++ source code for creating and navigating your own XML documents with CMarkup Lite.

Creating an XML Document

To create an XML document, instantiate a CMarkup object and call AddElem to create the root element. At this point, if you called AddElem("ORDER") your document would simply contain the empty ORDER element <ORDER/>. Then call AddChildElem to create elements under the root element (i.e. "inside" the root element, hierarchically speaking). The following example code creates an XML document and retrieves it into a CString:

Collapse Copy Code 
CMarkup xml;
xml.AddElem( "ORDER" );
xml.AddChildElem( "ITEM" );
xml.IntoElem();
xml.AddChildElem( "SN", "132487A-J" );
xml.AddChildElem( "NAME", "crank casing" );
xml.AddChildElem( "QTY", "1" );
CString csXML = xml.GetDoc();

This code generates the following XML. The root is the ORDER element; notice that its start tag <ORDER> is at the beginning and end tag </ORDER> is at the bottom. When an element is under (i.e. inside or contained by) a parent element, the parent's start tag is before it and the parent's end tag is after it. The ORDER element contains one ITEM element. That ITEM element contains 3 child elements: SN, NAME, and QTY.

Collapse Copy Code 
<ORDER>
<ITEM>
<SN>132487A-J</SN>
<NAME>crank casing</NAME>
<QTY>1</QTY>
</ITEM>
</ORDER>

As shown in the example, you can create elements under a child element by calling IntoElem to move your current main position to where the current child position is so you can begin adding under what was the child element. CMarkup maintains a current position in order to keep your source code shorter and simpler. This same position logic is used when navigating a document.

Navigating an XML Document

The XML string created in the above example can be parsed into a CMarkup object with the SetDoc method. You can also navigate it right inside the same CMarkup object where it was created; just call ResetPos if you want to reset the current position back to the beginning of the document.

In the following example, after populating the CMarkup object from the csDoc string, we loop through all ITEM elements under the ORDER element and get the serial number and quantity of each item:

Collapse Copy Code 
CMarkup xml;
xml.SetDoc( csXML );
while ( xml.FindChildElem("ITEM") )
{
    xml.IntoElem();
    xml.FindChildElem( "SN" );
    CString csSN = xml.GetChildData();
    xml.FindChildElem( "QTY" );
    int nQty = atoi( xml.GetChildData() );
    xml.OutOfElem();
}

For each item we find, we call IntoElem before interrogating its child elements, and then OutOfElem afterwards. As you get accustomed to this type of navigation you will know to check in your loops to make sure there is a corresponding OutOfElem call for every IntoElem call.

Adding Elements and Attributes

The above example for creating a document only created one ITEM element. Here is an example that creates multiple items loaded from a previously populated data source, plus a SHIPMENT information element in which one of the elements has an attribute. This code also demonstrates that instead of calling AddChildElem, you can call IntoElem and AddElem. It means more calls, but some people find this more intuitive.

Collapse Copy Code 
CMarkup xml;
xml.AddElem( "ORDER" );
xml.IntoElem(); // inside ORDER
for ( int nItem=0; nItem<aItems.GetSize(); ++nItem )
{
    xml.AddElem( "ITEM" );
    xml.IntoElem(); // inside ITEM
    xml.AddElem( "SN", aItems[nItem].csSN );
    xml.AddElem( "NAME", aItems[nItem].csName );
    xml.AddElem( "QTY", aItems[nItem].nQty );
    xml.OutOfElem(); // back out to ITEM level
}
xml.AddElem( "SHIPMENT" );
xml.IntoElem(); // inside SHIPMENT
xml.AddElem( "POC" );
xml.SetAttrib( "type", csPOCType );
xml.IntoElem(); // inside POC
xml.AddElem( "NAME", csPOCName );
xml.AddElem( "TEL", csPOCTel );

This code generates the following XML. The root ORDER element contains 2 ITEM elements and a SHIPMENT element. The ITEM elements both contain SN, NAME and QTY elements. The SHIPMENT element contains a POC element which has a type attribute, and NAME and TEL child elements.

Collapse Copy Code 
<ORDER>
<ITEM>
<SN>132487A-J</SN>
<NAME>crank casing</NAME>
<QTY>1</QTY>
</ITEM>
<ITEM>
<SN>4238764-A</SN>
<NAME>bearing</NAME>
<QTY>15</QTY>
</ITEM>
<SHIPMENT>
<POC type="non-emergency">
<NAME>John Smith</NAME>
<TEL>555-1234</TEL>
</POC>
</SHIPMENT>
</ORDER>

Finding Elements

The FindElem and FindChildElem methods go to the next sibling element. If the optional tag name argument is specified, then they go to the next element with a matching tag name. The element that is found becomes the current element, and the next call to Find will go to the next sibling or matching sibling after that current position.

When you cannot assume the order of the elements, you must reset the position in between calling the Find method. Looking at the ITEM element in the above example, if someone else is creating the XML and you cannot assume the SN element is before the QTY element, then call ResetChildPos() before finding the QTY element.

To find the item with a particular serial number, you can loop through the ITEM elements and compare the SN element data to the serial number you are searching for. This example differs from the original navigation example by calling IntoElem to go into the ORDER element and use FindElem("ITEM") instead of FindChildElem("ITEM"); either way is fine. And notice that by specifying the "ITEM" element tag name in the Find method we ignore all other sibling elements such as the SHIPMENT element.

Collapse Copy Code 
CMarkup xml;
xml.SetDoc( csXML );
xml.FindElem(); // ORDER element is root
xml.IntoElem(); // inside ORDER
while ( xml.FindElem("ITEM") )
{
    xml.FindChildElem( "SN" );
    if ( xml.GetChildData() == csFindSN )
        break; // found
}

Encodings

ASCII refers to the character codes under 128 that we have come to depend on, programming in English. Conveniently if you are only using ASCII, UTF-8 encoding is the same as your common ASCII set.

If you are using a character set not corresponding to one of the Unicode sets UTF-8, UTF-16 or UCS-2, you really should declare it in your XML declaration for the sake of interoperability and viewing it properly in Internet Explorer. Character sets like ISO-8859-1 (Western European) assign characters to the values in a byte between 128 and 255, so that every character still only uses one byte. Windows double-byte character sets such as GB2312, Shift_JIS and EUC-KR use one or two bytes per character. For these Windows charsets, put _MBCS in your preprocessor definitions and make sure your user's Operating System is set to the corresponding code page.

To prefix your XML document with an XML declaration such as <?xml version="1.0" encoding="ISO-8859-1"?>, pass it to SetDoc or the CMarkup constructor. Include a CRLF at the end as shown so that the root element goes on the next line.

Collapse Copy Code 
xml.SetDoc( "<?xml version=/"1.0/" encoding=/"ISO-8859-1/"?>/r/n" );
xml.AddElem( "island", "Cura�ao" );

Depth First Traversal

You can use the following code to loop through every element in your XML document. In the part of the code where you process the element, every element in the document (except the root element) will be encountered in depth first order. For illustrative purposes, it gets the tag name of the element. If you were searching for a particular element tag name you could break out of the loop at this point. "Depth first" means that it traverses all of an element's children before going to its sibling.

Collapse Copy Code 
BOOL bFinished = FALSE;
xml.ResetPos();
if ( ! xml.FindChildElem() )
    bFinished = TRUE;
while ( ! bFinished )
{
    // Process element
    xml.IntoElem();
    CString csTag = xml.GetTagName();

    // Next element (depth first)
    BOOL bFound = xml.FindChildElem();
    while ( ! bFound && ! bFinished )
    {
        if ( xml.OutOfElem() )
            bFound = xml.FindChildElem();
        else
            bFinished = TRUE;
    }
}

Loading and Saving Files

CMarkup Lite does not have Load and Save methods. To load a file, look in the CMarkupDlg::OnButtonParse method which loads a file into a string. Once you have it in a string, you can put it into the CMarkup object using SetDoc. To save it to a file, call GetDoc to get the string and then implement your own code to write the string to your file. When you need to implement any of your own project specific I/O error handling, streaming, permissions/locking, and charset conversion, it is actually good software design to keep this outside of the CMarkup class allowing CMarkup to remain a generic class.

The Test Dialog

The Markup.exe test bed for CMarkup is a Visual Studio 6.0 MFC project (also compiles in VS .NET too). When the dialog starts, it performs diagnostics in the RunTest function to test CMarkup in the context of the particular build options that have been selected. You can step through the RunTest function to see a lot of examples of how to use CMarkup. Use the Open and Parse button in the dialog to test a file.

In the following illustration, the Build Version is shown as "CMarkup Lite 6.5 Debug Unicode." This means that it is the debug version built with _UNICODE defined. The RunTest completed successfully. A parse error was encountered in the order_e.xml file. It also shows the load and parse times, and file size.

The Test Dialog keeps track of the last file parsed and the dialog screen position for convenience. This is kept in the registry under HKEY_CURRENT_USER/ Software/ First Objective Software/ Markup/ Settings.

How CMarkup Works

The CMarkup strategy is to leave the data in the document string and maintain a hierarchical arrangement of indexes mapping out the document.

  • increase speed: parse in one pass and maintain hierarchy of indexes
  • reduce overhead: do not copy or break up the text of the document

CMarkup parses the 250k play.xml sample document in about 40 milliseconds (1/25th of a second) on a 500Mhz machine, holding it as a single string, and allocating about 200k for a map of the 6343 elements. From then on, navigation does not require any parsing. As a rule of thumb, the map of indexes takes up approximately the same amount of memory as the document, so the memory footprint of the CMarkup object should settle down around 2 times the size of the document. For each element in the document a struct of eight integers (32 bytes) is maintained.

Collapse Copy Code 
int nStartL;
int nStartR;
int nEndL;
int nEndR;
int nReserved;
int iElemParent;
int iElemChild;
int iElemNext;

Look at the start and end tags in <QTY>1</QTY>. The struct contains the offsets of the left and right of both the start and end tags (i.e. all the < and > signs). The reserved integer is not currently used but could be used for a delete flag and/or level (i.e. depth) in the hierarchy to support indentation. The other three integers are indexes to the structs for the parent, child and next elements.

When the document is first parsed an array of these structs is built, and then as elements are modified and inserted in the XML, the structs are modified and added. Rather than allocating structs individually, they are allocated in an array using a "grow-by" mechanism to reduce the number of allocations to a handful. That is why integer array indexes rather than pointers are used for the links. Once an element is assigned an index in the array, that index does not change. So the index can be used as a way of referring to and locating an element

Release Notes

This release 6.5 of CMarkup Lite's public methods are backwards compatible with the previous release 6.1 posted here in August 2001 except for one rare usage of IntoElem. In 6.1, if you called IntoElem without a current child element, it would find the first child element. Now in 6.5 when there is no current child position, IntoElem puts the main position before the first child element so that a subsequent call to FindElem will not bypass the first element. So, the quick way to check this when upgrading is to scan all occurrences of IntoElem and make sure the previous CMarkup navigation call is FindChildElem before it. Or, if the child element was just created with AddChildElem then its okay because that sets the current child position too. For full details on this, see the IntoElem Changes in Release 6.3.

Other major changes since 6.1:

  • Fix: MBCS double-byte text x_TextToDoc *thanks knight_zhuge
  • Performance: parsing is roughly twice as fast
  • Debugging: see m_pMainDS and m_pChildDS class members while debugging to see string pointers showing current main and child positions
  • New Test Dialog interface with diagnostic results and load vs. parse times, and RunTest code for startup

License

CMarkup Lite is free for compiling into your commercial, personal and educational applications. Modify it as much as you like, but retain the copyright notice in the source code remarks. Redistribution of the modified or unmodified CMarkup Lite class source code is limited to your own development team and it cannot be made publicly available or distributable as part of any source code library or product, even if that offering is free. For source code products that derive from or utilize CMarkup Lite, please refer users to this article to obtain the source files for themselves. You are encouraged to discuss this source code and share enhancements here in the discussion board under this article. Enjoy!

<!-- Main Page Contents End -->

License

This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves. If in doubt please contact the author via the discussion board below.

A list of licenses authors might use can be found here

About the Author

Ben Bryant


Member 		Raised in Southern Ontario Canada. Bachelor of Science from the University of Toronto in Computer Science and Anthropology. Living near Washington D.C. in Virginia, USA.
Location: United States United States
from http://www.codeproject.com/KB/cpp/markupclass.aspx
分享到：
| VC解析XML--使用CMarkup类解析XML
评论
发表评论

您还没有登录,请您登录后再发表评论

相关推荐

    Markup.h和cpp读取xml

    本文将深入探讨如何使用"Markup.h"和"Markup.cpp"这两个文件来读取XML信息，以及它们在实际工程中的应用。 首先，"Markup.h"是头文件，其中包含了关于XML解析的相关声明，包括函数、类或者常量定义等。这些声明使得...

    在VC中通过第三方程序markup实现XML文档处理

    总结来说，“在VC中通过第三方程序markup实现XML文档处理”主要是指利用`markup.h`和`markup.cpp`这两个文件构建的轻量级XML解析器。这个解析器简单易用，能够帮助开发者快速地读取、遍历和操作XML文档，适用于那些...

    MarkUP ,用于VC环境下，读取和写入XMl文档文件 不错的程序.zip

    "MarkUP"程序由一系列源代码文件组成，包括Markup.cpp、MarkupDlg.cpp、MarkupMSXML.cpp、MarkupApp.cpp、StdAfx.cpp以及相关的头文件Markup.h和MarkupMSXML.h。这些文件共同构成了一个完整的VC++工程，其中： 1. ...

    xml之Markup操作类.rar

    在VS2015中，你可以将`Markup.cpp`和`Markup.h`添加到项目中，然后通过`#include "Markup.h"`来使用这个XML操作类。 开发人员在使用Markup类时，需要注意以下几点： 1. **正确解析XML**：确保提供的XML文档符合...

    C++XML工具库(markup库).rar

    它由两个主要文件组成：`Markup.h`和`Markup.cpp`。`Markup.h`包含了库的头文件，定义了API接口和相关的类结构；而`Markup.cpp`则实现了这些接口，提供了实际的XML处理功能。 在`Markup.h`中，我们可以期待看到一个...

    Markup113.zip

    库的核心包括两个主要文件：Markup.cpp 和 Markup.h。 Markup.h 文件是头文件，它定义了库的关键类和接口。在这个文件中，你可能会找到用于创建、解析和操作XML元素的类，如`MarkupNode`，以及一些辅助函数，如解析...

    运行xml文件的类AnimatePacker.h、AnimatePacker.cpp、Singleton.h

    这里的标题和描述提及了"运行xml文件的类AnimatePacker.h、AnimatePacker.cpp、Singleton.h"，这暗示我们讨论的是一个C++项目，其中包含了处理XML动画数据的类。 AnimatePacker.h和AnimatePacker.cpp是一对头文件...

    操作xml文件Markup类和例子

    例如，`Markup.cpp`和`Markup.h`两个文件可能分别定义了`Markup`类的实现和接口。 在`Markup.cpp`中，我们可以预见到包含的函数实现，如解析XML字符串或文件的`parse()`方法，创建新XML元素的`createElement()`，...

    xml.rar_Markup_c 文件操作类

    这个压缩包包含了一些关键文件，如Markup.cpp、MyXml.cpp、Markup.h和MyXml.h，它们都是为了实现XML文件的读取、解析和写入功能而设计的。 首先，我们来看`Markup.h`和`Markup.cpp`。这两个文件通常定义和实现了`...

    Markup(vc操作XML)

    在IT行业中，XML（eXtensible Markup Language）是一种用于存储和传输数据的...通过`Markup.cpp`和`Markup.h`中的实现，我们可以学习到如何在C++环境中高效地处理XML数据，这对于开发需要与XML数据交互的系统至关重要。

    CMarkup源码 XML创建及解析

    下载后取出里面的Markup.cpp和Markup.h，导入你的工程里面，CMarkup类就可以用了。其中的MSXML是另一套解析源码，主要使用COM，大家可以研究一下，我没用过这个。 另外从网上整理了一些CMark函数简介及相关实例，请...

    XML操作类简单易用完全源代码Markup

    在提供的压缩包中，有两个关键文件：`Markup.cpp`和`Markup.h`。`Markup.h`通常包含了类的定义，包括各种方法声明，而`Markup.cpp`则包含了这些方法的实现。以下是对Markup类库中可能包含的一些核心功能的详细介绍：...

    MFC Markup类的使用 读写XML文档

    XML（eXtensible Markup Language）是一种标准的数据交换格式，广泛应用于存储和传输结构化数据。`CMarkup`类使得MFC应用程序能够轻松地与XML文件交互，从而在不同系统和应用程序之间共享数据。 ### XML文档的基本...

    MarkUP ,用于VC环境下，读取和写入XMl文档文件。不错的程序.zip

    8. `Markup.h`和`MarkupMSXML.h`：头文件，包含了类定义和函数声明，供其他文件引用。 在C++中处理XML，开发者通常会面临解析XML结构、查找特定节点、修改节点值等挑战。MarkUP通过封装MSXML库，为开发者提供了简单...

    Cmarkup类,这个类包含了对xml操作的各种方法。

    在`Markup.cpp`和`Markup.h`这两个文件中，`Markup.h`是头文件，它定义了Cmarkup类的接口，包括类的声明和各种成员函数。`Markup.cpp`则是实现文件，包含了类的成员函数的具体实现。通常，开发者在自己的项目中只需...

    C++解析xml源码

    在提供的压缩包中，"Markup.cpp"和"Markup.h"可能是实现XML解析功能的源代码文件，它们可能包含了一个类或者一系列函数，用于解析XML文档。 在"Markup.h"中，可能会定义一个名为`Markup`的类，这个类通常会有一个...

    Markup112.zip

    2. **Markup.h**：这是CMarkup类的头文件，定义了类的结构、成员变量和公共接口。在编写使用CMarkup的代码时，需要包含这个头文件以获取必要的声明。 3. **evaluationlicense.txt**：这可能是一个评估许可证文件，...

    股票交易源码

    Markup.h XML解析 XMLDoc.h XML辅助 secret.h 主要包括一些注册机的加密算法和读取硬盘序列号的类。 NetDB.cpp 一些数据下载，安装的接口实现 HttpClt.cpp HTTP协议客户端类实现 InfoZip.cpp 压缩/解...

    yaml-cpp.tar.gz

    2. **包含头文件**：在C++源代码中，包含必要的头文件，如`#include &lt;yaml-cpp/yaml.h&gt;`。 3. **加载YAML**：使用`YAML::LoadFile`或`YAML::Load`函数解析YAML数据。 4. **操作YAML树**：通过`Node`对象访问和修改...

Magicbox
Global site tag (gtag.js) - Google Analytics