Dictionary and JSON format strings are converted to each other

In iOS development, and server interactions, dictionaries and JSON format strings are often used to convert to each other.

1. JSON format string to dictionary

+ (Nsdictionary *) dictionarywithjsonstring: (NSString *) jsonstring {        if (jsonstring = nil) {        return nil;    }        NSData *jsondata = [jsonstring datausingencoding:nsutf8stringencoding];        Nserror *err;        Nsdictionary *dic = [nsjsonserialization jsonobjectwithdata:jsondata                                                                                 options:nsjsonreadingmutablecontainers                                                                                   error:&err];        if (err) {                NSLog (@ "JSON parse failed:%@", err);                return nil;    }    return DIC;}

2. Dictionary to JSON format string

+ (nsstring*) Dictionarytojson: (nsdictionary *) dic{        nserror *parseerror = nil;        NSData *jsondata = [nsjsonserialization datawithjsonobject:dic options:nsjsonwritingprettyprinted error:& ParseError];        return [[NSString alloc] Initwithdata:jsondata encoding:nsutf8stringencoding];    }

Dictionary and JSON format strings are converted to each other