swift 字典转化jsonstring排序sort

有个需求需要把字典转成Json字符串，但是Json字符串Key值，按照ASCII码排序

一、系统自带JSONString方式，无法做到排序

let data :NSData! =try? JSONSerialization.data(withJSONObject: dictionary, options: [])asNSData!

let JSONString = NSString(data:dataasData,encoding: String.Encoding.utf8.rawValue)

return JSONString!asString

二、iOS11 开始支持排序参数传入
if #available(iOS 11.0, *) {

let data : NSData! = try? JSONSerialization.data(withJSONObject: dictionary, options: JSONSerialization.WritingOptions.sortedKeys) as NSData!

let JSONString = NSString(data:data as Data,encoding: String.Encoding.utf8.rawValue)

return JSONString! as String

}

WritingOptions中包含排序

三、为了适配各种版本，自定义拼接

func creatJsonString(dict: [String:Any]) ->String{

if(!JSONSerialization.isValidJSONObject(dict)) {

print("无法解析出JSONString")

return""

}

var namedPaird = [String]()

let sortedKeysAndValues = dict.sorted{$0.0< $1.0}

for(key, value) in sortedKeysAndValues {

if value is [String:Any] {

namedPaird.append("\"\(key)\":\(self.creatJsonString(dict: valueas! [String:Any]))")

}else if value is [Any] {

namedPaird.append("\"\(key)\":\(value)")

}else{

namedPaird.append("\"\(key)\":\"\(value)\"")

}

}

let returnString = namedPaird.joined(separator:",")

return"{\(returnString)}"

}