Iosjson (convert a dictionary or array into a JSON string)

1. Convert NSDictionary or NSArray into a JSON string and convert the dictionary or array into a JSON string

1. Convert NSDictionary or NSArray to a JSON string // convert the dictionary or array to a JSON string-(NSData *) toJSONData :( id) theData {NSError * error = nil; NSData * jsonData = [NSJSONSerialization dataWithJSONObject: theData options: NSJSONWritingPrettyPrinted error: if

1. Convert NSDictionary or NSArray into a JSON string

// Convert a dictionary or array into a JSON string

-(NSData *) toJSONData :( id) theData {



NSError * error = nil;

NSData * jsonData = [NSJSONSerialization dataWithJSONObject: theData

Options: NSJSONWritingPrettyPrinted

Error: & error];



If ([jsonData length]> 0 & error = nil ){

Return jsonData;

} Else {

Return nil;

}

}

With this method, we can get the desired JSON string

NSString * jsonString = [[NSString alloc] initWithData: jsonData

Encoding: NSUTF8StringEncoding];


2. Convert the JSON string to NSDictionary or NSArray

Convert NSString to NSData

[JsonString dataUsingEncoding: NSASCIIStringEncoding];



// Convert a JSON string into a dictionary or Array

-(Id) toArrayOrNSDictionary :( NSData *) jsonData {

NSError * error = nil;

Id jsonObject = [NSJSONSerialization JSONObjectWithData: jsonData

Options: NSJSONReadingAllowFragments

Error: & error];



If (jsonObject! = Nil & error = nil ){

Return jsonObject;

} Else {

// Resolution Error

Return nil;

}


}

3. encapsulate JSON strings with NSArray and NSDictionary operations

Of course, there are also many times when we define these operations in a classification of NSObject and NSString respectively.

Direct paste:

1. Convert NSString to NSArray or NSDictionary

# Import "NSString + JSONCategories. h"


@ Implementation NSString (JSONCategories)


-(Id) JSONValue;

{

NSData * data = [self dataUsingEncoding: NSUTF8StringEncoding];

_ Autoreleasing NSError * error = nil;

Id result = [NSJSONSerialization JSONObjectWithData: data options: kNilOptions error: & error];

If (error! = Nil) return nil;

Return result;

}

@ End


2. Convert NSArray or NSDictionary to NSString

# Import "NSObject + JSONCategories. h"


@ Implementation NSObject (JSONCategories)


-(NSData *) JSONString;

{

NSError * error = nil;

Id result = [NSJSONSerialization dataWithJSONObject: self

Options: kNilOptions error: & error];

If (error! = Nil) return nil;

Return result;

}

@ End
<无>

1. Convert NSDictionary or NSArray to a JSON string // convert the dictionary or array to a JSON string-(NSData *) toJSONData :( id) theData {NSError * error = nil; NSData * jsonData = [NSJSONSerialization dataWithJSONObject: theData options: NSJSONWritingPrettyPrinted error: & error]; if ([jsonData length]> 0 & error = nil) {return jsonData ;} else {return nil;} returns the result using this method. We can get the desired JSON string NSString * jsonString = [[NSString alloc] initWithData: jsonData encodin G: NSUTF8StringEncoding]; 2. convert a JSON string to NSDictionary or NSArray to NSData [jsonString dataUsingEncoding: NSASCIIStringEncoding]; // convert the JSON string to a dictionary or array-(id) toArrayOrNSDictionary :( NSData *) jsonData {NSError * error = nil; id jsonObject = [NSJSONSerialization JSONObjectWithData: jsonData options: response error: & error]; if (jsonObject! = Nil & error = nil) {return jsonObject;} else {// resolution error return nil ;}} 3. encapsulate the JSON string and NSArray and NSDictionary operations, there are also many times when we define these operations in a classification of NSObject and NSString respectively: 1. convert NSString to NSArray or NSDictionary # import "NSString + JSONCategories. h "@ implementation NSString (JSONCategories)-(id) JSONValue; {NSData * data = [self dataUsingEncoding: Custom]; _ autoreleasing NSError * error = nil; id result = [NSJ SONSerialization JSONObjectWithData: data options: kNilOptions error: & error]; if (error! = Nil) return nil; return result;} @ end2. convert NSArray or NSDictionary to NSString # import "NSObject + JSONCategories. h "@ implementation NSObject (JSONCategories)-(NSData *) JSONString; {NSError * error = nil; id result = [NSJSONSerialization dataWithJSONObject: self options: kNilOptions error: & error]; if (error! = Nil) return nil; return result;} @ end