我有一个字典,我需要通过使用字典生成一个JSON字符串。可以转换吗?你们能帮帮我吗?
当前回答
可以传递数组或字典。这里,我使用NSMutableDictionary。
NSMutableDictionary *contentDictionary = [[NSMutableDictionary alloc]init];
[contentDictionary setValue:@"a" forKey:@"b"];
[contentDictionary setValue:@"c" forKey:@"d"];
为了从NSDictionary或NSArray中生成JSON字符串,你不需要导入任何第三方框架。只需使用以下代码:-
NSError *error;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:contentDictionary // Here you can pass array or dictionary
options:NSJSONWritingPrettyPrinted // Pass 0 if you don't care about the readability of the generated string
error:&error];
NSString *jsonString;
if (jsonData) {
jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
//This is your JSON String
//NSUTF8StringEncoding encodes special characters using an escaping scheme
} else {
NSLog(@"Got an error: %@", error);
jsonString = @"";
}
NSLog(@"Your JSON String is %@", jsonString);
其他回答
从ISO7开始,至少你可以用NSJSONSerialization轻松做到这一点。
这是Swift 4的版本
extension NSDictionary{
func toString() throws -> String? {
do {
let data = try JSONSerialization.data(withJSONObject: self, options: .prettyPrinted)
return String(data: data, encoding: .utf8)
}
catch (let error){
throw error
}
}
}
使用的例子
do{
let jsonString = try dic.toString()
}
catch( let error){
print(error.localizedDescription)
}
或者如果你确定它是有效的字典,那么你可以使用
let jsonString = try? dic.toString()
可以传递数组或字典。这里,我使用NSMutableDictionary。
NSMutableDictionary *contentDictionary = [[NSMutableDictionary alloc]init];
[contentDictionary setValue:@"a" forKey:@"b"];
[contentDictionary setValue:@"c" forKey:@"d"];
为了从NSDictionary或NSArray中生成JSON字符串,你不需要导入任何第三方框架。只需使用以下代码:-
NSError *error;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:contentDictionary // Here you can pass array or dictionary
options:NSJSONWritingPrettyPrinted // Pass 0 if you don't care about the readability of the generated string
error:&error];
NSString *jsonString;
if (jsonData) {
jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
//This is your JSON String
//NSUTF8StringEncoding encodes special characters using an escaping scheme
} else {
NSLog(@"Got an error: %@", error);
jsonString = @"";
}
NSLog(@"Your JSON String is %@", jsonString);
注:这个答案是在iOS 5发布之前给出的。
获取json-framework并执行以下操作:
#import "SBJsonWriter.h"
...
SBJsonWriter *jsonWriter = [[SBJsonWriter alloc] init];
NSString *jsonString = [jsonWriter stringWithObject:myDictionary];
[jsonWriter release];
myDictionary就是你的字典。
您也可以通过在调试器中输入以下内容即时执行此操作
po [[NSString alloc] initWithData:[NSJSONSerialization dataWithJSONObject:yourDictionary options:1 error:nil] encoding:4];