C # processing XML

Last Update:2018-12-06 Source: Internet

Author: User

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This article describes how to process XML documents in C.
First, we first build an XML document, as shown below:

<? XML version = "1.0" encoding = "UTF-8"?>
<Peoplelist>
<Person>
<Name> Tom Stafford </Name>
<Title> CFO </title>
</Person>
<Person>
<Name> Jane goodwill </Name>
<Title> CEO </title>
</Person>
<Person>
<Name> Tim Daly </Name>
<Title> CTO </title>
<Title2> cto0 </title2>
</Person>
<Person>
<Name> JOHN graver </Name>
<Title> CSO </title>
</Person>
</Peoplelist>

Save it as: people. XML ,:)

(1) Find the specified node in the XML document
For example, to search for a user named 'Tim daly' <title2>, the specific procedure is as follows.
----
<% @ Page Language = "C #" %>
<% @ Import namespace = "system. xml" %>
<% @ Import namespace = "system. xml. XSL" %>
<% @ Import namespace = "system. xml. XPath" %>
<Script language = "C #" runat = "server">
Void page_load (Object OBJ, eventargs E)
{
String xmlfile = "People. xml", XPath;
XPath = server. mappath (xmlfile );
Xmldocument mydoc = new xmldocument (); // defines an xmldocument object.
Mydoc. Load (XPath );
Message. Text = mydoc. selectsinglenode ("// person [name = 'Tim daly']"). childnodes. Item (2). innertext ;}
</SCRIPT>
<Asp: Label id = "message" forecolor = "red" runat = "server"/>

Explanation:

// Represents any layer of sub-nodes. In this way, you can quickly find what you want.
Selectsinglenode is used to find a single node. selectnodes can find many nodes.

(2) Fill the list box with XML documents. Only the <Name> node is used here.

<% @ Page Language = "C #" DEBUG = "true" %>
<% @ Import namespace = "system. Collections" %>
<% @ Import namespace = "system. xml" %>
<HTML>
<Head>
<Script language = "C #" runat = "server">
Private void page_load (Object sender, eventargs E)
{
If (! Ispostback)
{
Arraylist values = new arraylist (); // use it as a data source
Xmldocument Doc = new xmldocument (); // represents an XML document
Doc. Load (server. mappath ("People. xml "));

// Returns an xmlnodelist set that contains a list of all child elements matching the specified name.
Xmlnodelist elemlist = Doc. getelementsbytagname ("name"); // system. xml namespace

For (INT I = 0; I <elemlist. Count; I ++)
{
Values. Add (elemlist [I]. innerxml );
}
Listbox1.datasource = values;
Listbox1.databind ();
}
}

// Obtain the text of the list item and selected item
Private void submitbtn_click (Object sender, eventargs E)
{
If (listbox1.selectedindex>-1)
Label1.text = "selected option:" + listbox1.selecteditem. Text + "<p> ";
}
</SCRIPT>
</Head>
<Body>
<Form runat = Server>
<H3> Data Binding ListBox <Asp: Label id = "label1" font-name = "verdana" font-size = "10pt" runat = "server"/>
<Asp: ListBox id = "listbox1" selectionmode = "single" rows = "1" runat = "server"/>
<Asp: button id = "button1" text = "Submit" onclick = "submitbtn_click" runat = "server"/>
</Form>
</Body>
</Html>
========================================================== ======
(3) read XML documents into repeater through dataset.
You can also read it into dataset. The principle is the same.
<% @ Import namespace = "system" %>
<% @ Import namespace = "system. Io" %>
<% @ Import namespace = "system. Data" %>
<% @ Page Language = "C #" %>
<HTML>
<Head>
<Title> Read to repeater </title>
<Script language = "C #" runat = Server>
Public void page_load (Object OBJ, eventargs E)
{
String XPath = "DB/people. xml ";
Try
{
Dataset DS = new dataset ();
Filestream FS = new filestream (server. mappath (XPath), filemode. Open, fileaccess. Read, fileshare. readwrite );
DS. readxml (New streamreader (FS ));
FS. Close ();
Trace. Warn ("Number of table records", convert. tostring (Ds. Tables [0]. Rows. Count ));

Mydatalist. datasource = Ds. Tables [0]. defaultview;
Mydatalist. databind ();
}
Catch (exception ed)
{
Response. Write ("<font color = # ff0000>" + ed. tostring () + "</font> ");
}
}

</SCRIPT>
</Head>
<Body>
<Asp: repeater id = "mydatalist" runat = "server">
<Headertemplate>
<H5> viewer details </H5>
</Headertemplate>
<Itemtemplate>
<Br>
<Table class = "mainheads" width = "60%" style = "Font: 8pt verdana">
<Tr style = "background-color: # ffffcc">
<TD> name: </TD>
<TD> <% # databinder. eval (container. dataitem, "name") %> </TD>
</Tr>
<Tr style = "background-color: # ffffcc">
<TD> title: </TD>
<TD> <% # databinder. eval (container. dataitem, "title") %> </TD>
</Tr>
<Tr style = "background-color: # ffffcc">
<TD> title2: </TD>
<TD> <% # databinder. eval (container. dataitem, "title2") %> </TD>
</Tr>
</Table> <br>
</Itemtemplate>
</ASP: repeater>
</Body>
</Html>

---------
(4) Save the data in repeater to XML. Similarly, you can also use the data in dataset.
In this example, a new row is added and the edited result is saved to XML
<% @ Import namespace = "system" %>
<% @ Import namespace = "system. Io" %>
<% @ Import namespace = "system. Data" %>
<% @ Page Language = "C #" trace = "true" %>
<HTML>
<Head>
<Title> Saurabh's XML counter script </title>
<Script language = "C #" runat = Server>
Public void page_load (Object OBJ, eventargs E)
{
String datafile = "DB/people. xml ";
If (! Page. ispostback)
{
Try {
Dataset DS = new dataset ();
Filestream fint;
Fint = new filestream (server. mappath (datafile), filemode. Open, fileaccess. Read, fileshare. readwrite );
DS. readxml (fint );
Fint. Close ();

If (session ["counter"] = NULL)
{
Datarow DR = Ds. Tables [0]. newrow ();

Dr ["name"] = "myname ";
Dr ["title"] = "test ";
Dr ["title2"] = "Test2 ";

DS. Tables [0]. Rows. Add (DR );
Filestream fout;
Fout = new filestream (server. mappath (datafile), filemode. Open, fileaccess. Write, fileshare. readwrite );
DS. writexml (fout, xmlwritemode. writeschema );
Fout. Close ();
Session ["counter"] = "set ";
}
Trace. Warn ("Number of table records", DS. Tables [0]. Rows. Count. tostring ());
}
Catch (exception EDD)
{
Response. Write ("<font color = # ff0000>" + EDD. tostring () + "</font> ");
}
}
}

</SCRIPT>
</Body>
</Html>

----------------------
(5) read XML data in the URL
C # the XML data in the URL is read. Normally, static XML files are read, but XML data is updated at any time in the securities field.
For example, if a third party wants us to provide XML data, we will develop it for the second party, and the third party will provide us with a URL, which is in XML format and contains the required data.
The example here is to read the URL on csdn.
Using system;
Using system. xml;
Namespace consoleapplication5
{
Class class1
{
[Stathread]
Static void main (string [] ARGs)
{
Xmldocument Doc = new xmldocument ();
Doc. Load ("http://www.csdn.net/expert/topic/1094/1094085.xml? Temp =. 9642145 ");
Doc. Save (console. Out );
}
}
}
In this way, the C # program will display the XML uploaded from the remote ASP page in console. Out (console output.

This article is an English version of an article which is originally in the Chinese language on aliyun.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to info-contact@alibabacloud.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

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C # processing XML

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