Basic XML operations

 

<? XML version = "1.0" encoding = "gb2312"?>
<Bookstore>
<Book genre = "Fantasy" ISBN = "2-3631-4">
<Title> Oberon's legacy </title>
<Author> corets, Eva </author>
<Price> 5.95 </price>
</Book>
</Bookstore>

1. Insert a <book> node to the <bookstore> node:
Xmldocument xmldoc = new xmldocument ();
Xmldoc. Load ("Bookstore. xml ");
Xmlnode root = xmldoc. selectsinglenode ("Bookstore"); // query <bookstore>
Xmlelement xe1 = xmldoc. createelement ("book"); // create a <book> node
Xe1.setattribute ("genre", "lizan red"); // you can specify the genre attribute of the node.
Xe1.setattribute ("ISBN", "2-3631-4"); // you can specify the ISBN attribute of the node.

Xmlelement xesub1 = xmldoc. createelement ("title ");
Xesub1.innertext = "Cs from entry to entry"; // set a text node
Xe1.appendchild (xesub1); // Add it to the <book> node
Xmlelement xesub2 = xmldoc. createelement ("author ");
Xesub2.innertext = "Hou Jie ";
Xe1.appendchild (xesub2 );
Xmlelement xesub3 = xmldoc. createelement ("price ");
Xesub3.innertext = "58.3 ";
Xe1.appendchild (xesub3 );

Root. appendchild (xe1); // Add it to the <bookstore> node
Xmldoc. Save ("Bookstore. xml ");
// ================================================ ==========
Result:
<? XML version = "1.0" encoding = "gb2312"?>
<Bookstore>
<Book genre = "Fantasy" ISBN = "2-3631-4">
<Title> Oberon's legacy </title>
<Author> corets, Eva </author>
<Price> 5.95 </price>
</Book>
<Book genre = "Li zanhong" ISBN = "2-3631-4">
<Title> Cs from entry to entry </title>
<Author> Hou Jie </author>
<Price> 58.3 </price>
</Book>
</Bookstore>

2. Modify the node: Change the genre value of the node whose genre attribute value is "Li zenhong" to "Update Li zenhong ", modify the text of the child node <author> of the node to "Yasheng ".
Xmlnodelist nodelist = xmldoc. selectsinglenode ("Bookstore"). childnodes; // obtain all the subnodes of the bookstore Node
Foreach (xmlnode Xn in nodelist) // traverses all subnodes
{
Xmlelement Xe = (xmlelement) xn; // converts the subnode type to the xmlelement type
If (Xe. getattribute ("genre") = "") // If the genre attribute value is ""
{
Xe. setattribute ("genre", "Update lizan red"); // you can change this attribute to "Update lizan red"

Xmlnodelist NLS = Xe. childnodes; // continue to obtain all the child nodes of the Xe subnode
Foreach (xmlnode xn1 in NLS) // traverse
{
Xmlelement xe2 = (xmlelement) xn1; // Conversion Type
If (xe2.name = "author") // If you find
{
Xe2.innertext = "Yasheng"; // modify
Break; // find and exit.
}
}
Break;
}
}

Xmldoc. Save ("Bookstore. xml"); // save.
// ================================================ ================
The final result is:
<? XML version = "1.0" encoding = "gb2312"?>
<Bookstore>
<Book genre = "Fantasy" ISBN = "2-3631-4">
<Title> Oberon's legacy </title>
<Author> corets, Eva </author>
<Price> 5.95 </price>
</Book>
<Book genre = "Update Li zanhong" ISBN = "2-3631-4">
<Title> Cs from entry to entry </title>
<Author> Yasheng </author>
<Price> 58.3 </price>
</Book>
</Bookstore>

3. Delete the genre attribute of the <book genre = "Fantasy" ISBN = "2-3631-4"> node, delete the <book genre = "Update lizan red" ISBN = "2-3631-4"> node.
Xmlnodelist xnl = xmldoc. selectsinglenode ("Bookstore"). childnodes;

Foreach (xmlnode Xn in xnl)
{
Xmlelement Xe = (xmlelement) xn;
If (Xe. getattribute ("genre") = "Fantasy ")
{
Xe. removeattribute ("genre"); // Delete genre attributes
}
Else if (Xe. getattribute ("genre") = "Update lizanhong ")
{
Xe. removeall (); // delete all content of the node
}
}
Xmldoc. Save ("Bookstore. xml ");
// ================================================ =====
The final result is:
<? XML version = "1.0" encoding = "gb2312"?>
<Bookstore>
<Book ISBN = "2-3631-4">
<Title> Oberon's legacy </title>
<Author> corets, Eva </author>
<Price> 5.95 </price>
</Book>
<Book>
</Book>
</Bookstore>

4. display all data.
Xmlnode xn = xmldoc. selectsinglenode ("Bookstore ");

Xmlnodelist xnl = xn. childnodes;

Foreach (xmlnode xnf in xnl)
{
Xmlelement Xe = (xmlelement) xnf;
Console. writeline (Xe. getattribute ("genre"); // display attribute values
Console. writeline (Xe. getattribute ("ISBN "));

Xmlnodelist xnf1 = Xe. childnodes;
Foreach (xmlnode xn2 in xnf1)
{
Console. writeline (xn2.innertext); // displays the child node text.
}
}