(Objective-C) Removing / Deleting Child Nodes from XML

Demonstrates various methods for removing child nodes from an XML document.

The input XML, available at http://www.chilkatsoft.com/data/fruit.xml, is this:

<root>
    <fruit color="red">apple</fruit>
    <fruit color="green">pear</fruit>
    <veg color="orange">carrot</veg>
    <meat animal="cow">beef</meat>
    <xyz>
        <fruit color="blue">blueberry</fruit>
        <veg color="green">broccoli</veg>
    </xyz>
    <fruit color="purple">grape</fruit>
    <cheese color="yellow">cheddar</cheese>
</root>

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#import <CkoXml.h>

CkoXml *xml = [[CkoXml alloc] init];
CkoXml *xyz = 0;

BOOL success;
// The sample input XML is available at http://www.chilkatsoft.com/data/fruit.xml
success = [xml LoadXmlFile: @"fruit.xml"];
if (success != YES) {
    NSLog(@"%@",xml.LastErrorText);
    return;
}

// The RemoveChild method removes (discards) all direct
// children having the specified tag:
[xml RemoveChild: @"fruit"];

// Show the resulting XML:
NSLog(@"%@",@"Result with all direct children having a tag equal to \"fruit\" removed:");
NSLog(@"%@",[xml GetXml]);

// The XML with the "fruit" direct children removed is shown below:
// Notice that the "fruit" node beneath "xyz" was not removed.
// This correct because it was not a direct child of the calling node.

// <root>
//     <veg color="orange">carrot</veg>
//     <meat animal="cow">beef</meat>
//     <xyz>
//         <fruit color="blue">blueberry</fruit>
//         <veg color="green">broccoli</veg>
//     </xyz>
//     <cheese color="yellow">cheddar</cheese>
// </root>

// --------------------------------------------------------------------------
// Restore the original XML:
success = [xml LoadXmlFile: @"fruit.xml"];

// The RemoveChildWithContent method removes the child
// having the exact content specified, regardless of the tag.  
// For example:
[xml RemoveChildWithContent: @"pear"];

// Show the resulting XML:
NSLog(@"%@",@"Result with the node containing \"pear\" removed:");
NSLog(@"%@",[xml GetXml]);

// --------------------------------------------------------------------------
// Restore the original XML:
success = [xml LoadXmlFile: @"fruit.xml"];

// The RemoveChildByIndex method removes the Nth direct
// child.  Indexing begins at 0.  The "xyz" child is at index 4:
[xml RemoveChildByIndex: [NSNumber numberWithInt: 4]];

// Show the resulting XML:
// Notice that the entire "xyz" subtree is removed.
NSLog(@"%@",@"Result with the node at index 4 removed:");
NSLog(@"%@",[xml GetXml]);

// --------------------------------------------------------------------------
// Restore the original XML:
success = [xml LoadXmlFile: @"fruit.xml"];

// Navigate to the node with tag "xyz"
xyz = [xml FindChild: @"xyz"];

// Remove the "xyz" subtree making it it's own XML document
// with the "xyz" node at the root:
[xyz RemoveFromTree];

// Show both XML documents:
NSLog(@"%@",[xyz GetXml]);
NSLog(@"%@",[xml GetXml]);

// Also, the TreeId property is an integer value assigned
// to nodes in an XML document.  All nodes belonging to
// the same XML document will have the same TreeId.
// Notice that the "xyz" node now has a different TreeId:
NSLog(@"%@%d",@"xyz TreeId = ",[xyz.TreeId intValue]);
NSLog(@"%@%d",@"xml TreeId = ",[xml.TreeId intValue]);