Parsing Html url in iphone - html

Question

How do I parse an html file?
I need the data in between span tag.
<div id=currency_converter_result>1 AED = <span class=bld>0.4765 ANG</span>

Answer 1

If you need only tag 'span' you can use NSRegularExpression such as this one
NSString *html = #"<div id=currency_converter_result>1 AED = <span class=bld>0.4765 ANG</span>";
NSRegularExpression *regex = [NSRegularExpression
regularExpressionWithPattern:#"<span[^>]*>(.+?)</span>"
options:NSRegularExpressionCaseInsensitive
error:nil];
NSTextCheckingResult *textCheckingResult = [regex firstMatchInString:html options:0 range:NSMakeRange(0, html.length)];
NSLog(#"found: '%#'", [html substringWithRange:[textCheckingResult rangeAtIndex:1]]);
or, I prefer to create a NSDictionary from xml or html data and work with it. You can do it with XML-to-NSDictionary library.

Answer 2

Check out this:
https://github.com/zootreeves/Objective-C-HMTL-Parser
Basic Usage :
NSError *error = nil;
NSString *htmlString =
#"<div id=currency_converter_result>1 AED = <span class=bld>0.4765 ANG</span>";
HTMLParser *p = [[HTMLParser alloc] initWithString:htmlString error:&error];
if (error) {
NSLog(#"Error: %#", error);
return;
}
HTMLNode *bodyNode = [p body];
NSArray *spanNodes = [bodyNode findChildTags:#"span"];
for (HTMLNode *spanNode in spanNodes) {
if ([[spanNode getAttributeNamed:#"class"] isEqualToString:#"bld"]) {
NSLog(#"%#", [spanNode rawContents]); //Answer to second question
}
}

Answer 3

Since XHTML is XML, you can consider using NSXMLParser:
#interface HTMLParser: NSObject <NSXMLParserDelegate> // or whichever superclass you have
{
// own declarations
NSMutableString *str;
NSXMLParser *parser;
}
// somewhere in a method of self, for example, init, or something named -(void) parseHtml
- (void) parseHtml
{
parser = [[NSXMLParser alloc] initWithData:[#"<div id=currency_converter_result>1 AED = <span class=bld>0.4765 ANG</span>" dataUsingEncoding:NSUTF8StringEncoding]];
// of course you can substitute any string you want here, for example, the result of [NSString stringWithContentsOfFile:#"inex.html"] or whatever you need.
parser.delegate = self;
[parser parse];
[parser release];
}
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qualifiedName attributes:(NSDictionary *)attributeDict
{
if ([elementName isEqualToString:#"span"] && [[attributeDict objectForKey:#"class"] isEqualToString:#"bld"])
{
str = [NSMutableString string];
}
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
[str appendString:string];
}
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
if ([elementName isEqualToString:#"span"])
{
// now str contains the value you want!
DoSomethingWith(str);
}
}
Hope this helps.