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POParsing a JSON array into a NSDictionary
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  1. POParsing a JSON array into a NSDictionary
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    copied!<p>I'm working with the Weather Underground API to make an app and I've hit a snag while parsing the block relating to severe alerts. The JSON uses key-value pairs that have sub key value pairs -- which haven't been a problem for me, as I can make subsequent NSDictionaries out of those -- but the entry for severe alerts has proven problematic. See below:</p> <pre><code>"alerts": [ { "type": "WAT", "description": "Flash Flood Watch", "date": "3:13 PM EDT on April 28, 2012", "date_epoch": "1335640380", "expires": "8:00 AM EDT on April 29, 2012", "expires_epoch": "1335700800", "message": "\u000A...Flash Flood Watch in effect through Sunday morning...\u000A\u000AThe National Weather Service in Charleston has issued a\u000A\u000A* Flash Flood Watch for portions of northeast Kentucky... (Note: I trimmed this for length's sake), "phenomena": "FF", "significance": "A" } ] </code></pre> <p>The "alerts" pair differs from others I've been able to parse because it has this <strong>[ ] bracket</strong> surrounding the sub-values and I'm not sure how to clear it so I can access the subvalues. In the other examples I've been able to parse, it only has the <strong>{ } brackets</strong>, and not both the { } and [ ] brackets. For reference, the brackets are always present -- even when there are no severe weather alerts... in that instance the "alerts" pair returns the brackets [ ] with no sub-pairs present.</p> <p>Is there a way I can remove the [ ] brackets from the NSDictionary, or otherwise ignore them? Any advice would be appreciated!</p> <hr> <p>For reference and troubleshooting help, here's how I'm parsing the rest of the JSON document successfully:</p> <p>1) Create an NSDictionary from the raw JSON</p> <pre><code>//Process Weather Call NSError* error; NSDictionary* json = [NSJSONSerialization JSONObjectWithData:responseData options:kNilOptions error:&amp;error]; </code></pre> <p>2) Create subsequent dictionaries for nested json pairs</p> <pre><code>NSDictionary *current_observation = [json objectForKey:@"current_observation"]; </code></pre> <p>3) Assign values</p> <pre><code>NSString* weather; weather = [current_observation objectForKey:@"weather"]; </code></pre> <p>So the end result would be a string that says "Partly Cloudy" or something, along with numerous related weather values that I haven't shown. These parse successfully because they only have the scope brackets { }, and not the [ ] brackets.</p>
 

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