How to get image url from Yahoo weather forecast XML document?

Question

I'm getting weather information from yahoo weather and i'm able to parse temperature info from document but having problem to fetch image url from <escription> element i.e.

<description>
<![CDATA[
<img src="http://l.yimg.com/a/i/us/we/52/28.gif"/><br /> <b>Current Conditions:</b><br /> Mostly Cloudy, 61 F<BR /> <BR /><b>Forecast:</b><BR /> Thu - Showers. High: 66 Low: 48<br /> Fri - AM Light Rain. High: 52 Low: 37<br /> Sat - Partly Cloudy. High: 61 Low: 47<br /> Sun - AM Clouds/PM Sun. High
]]>
<![CDATA[
: 66 Low: 48<br /> Mon - PM Showers. High: 62 Low: 50<br /> <br /> <a href="http://us.rd.yahoo.com/dailynews/rss/weather/Hakuba_Station__JP/*http://weather.yahoo.com/forecast/JAXX0105_f.html">Full Forecast at Yahoo! Weather</a><BR/><BR/> (provided by <a href="http://www.weather.com" >The Weather Channel</a>)<br/>
]]>
</description>

Please not that i'm using NSXMLParser for parsing the MXL document.

score 1 · Answer 1 · answered Nov 06 '14 at 10:04

1

In your NSXMLParserDelegate, you can call the delegate method foundCDATA and handle the data there.

- (void)parser:(NSXMLParser *)parser foundCDATA:(NSData *)CDATABlock {
      NSString *cdataString = [[NSString alloc] initWithData:CDATABlock encoding:NSUTF8StringEncoding];
      // Do extraction of image src here
}

You can check the documentation for the delegate method here: NSXMLParserDelegate

answered Nov 06 '14 at 10:04

rudedude

723
4
18

do i need to parse html to get img src? If yes could you please give me some reference on how to do that? – Blios Nov 06 '14 at 10:30
Do you still need a parser method? – rudedude Nov 07 '14 at 01:28

score 1 · Accepted Answer · answered Nov 06 '14 at 10:44

Based on @haras.prasad answer i solved this problem using NSXMLParser delegate and NSRegularExpression

- (void)parser:(NSXMLParser *)parser foundCDATA:(NSData *)CDATABlock {
    NSString *cdataString = [[NSString alloc] initWithData:CDATABlock encoding:NSUTF8StringEncoding];
    // Do extraction of image src here
    NSError* error;
    NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"(<img\\s[\\s\\S]*?src\\s*?=\\s*?['\"](.*?)['\"][\\s\\S]*?>)+?"
                                                                           options:NSRegularExpressionCaseInsensitive
                                                                             error:&error];

    NSString *imageUrlString = nil;
    NSTextCheckingResult *match = [regex firstMatchInString:cdataString options:0 range:NSMakeRange(0, [cdataString length])];
    if (match)
    {
        imageUrlString = [cdataString substringWithRange:[match rangeAtIndex:2]];

        self.iconUrl = imageUrlString;
    }

}

score 0 · Answer 3 · answered Nov 06 '14 at 09:56

You can get CDATA string :

NSString *prefix = @"<![CDATA[";
if ([xmlString hasPrefix:prefix]) {
    NSString *cdataString = [_factString substringWithRange:NSMakeRange((prefix.length+1), xmlString.length - 3 -(prefix.length+1))];
    // Do stuff with CDATA here...
    NSLog(@"%@", cdataString);
}

How to get image url from Yahoo weather forecast XML document?

3 Answers3