Swift小项目的细碎知识点

一、GCD延时调用

HUD_DISMISS_TIME为延时执行的时间

DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + HUD_DISMISS_TIME, execute: {
      //在这里做需要延时的操作
})

二、GCD队列

self.group = DispatchGroup.init()
let holiday1 = DispatchQueue(label: "holiday")
holiday1.async(group: group) {
            //操作1
}

let holiday2 = DispatchQueue(label: "holiday")
holiday2.async(group: group) {
            //操作2
}

self.group?.notify(queue: DispatchQueue.main) {
        //完成上面的操作，通知开始下一步操作
}

三、判断一个对象是否为空

if dicData is NSNull {
        //
}

四、日期格式化

//MARK:日期格式化-日期转字符串
    func dateFormatter(_ date:Date ,formatter:String) ->String{
        let dateformatter = DateFormatter()
        dateformatter.dateFormat = formatter
        let d = dateformatter.string(from: date)
        return d
    }

    //MARK:日期格式化-日期转日期
    func dateFormatterForDate(_ date:Date,formatter:String) -> Date {
        let dateformatter = DateFormatter()
        dateformatter.dateFormat = formatter
        let datee = date
        return datee
    }

    //MARK:日期格式化-字符串转日期
    func stringToDate(_ string:String,formatter:String) ->Date{
        let dateformatter = DateFormatter()
        dateformatter.dateFormat = formatter
        let date:Date = dateformatter.date(from: string)!
        return date
    }

五 、定义闭包（block块）类型时，当参数类型为Dictionary，如下，

typealias RequestSuccess = (_ success:Dictionary) ->Void

会出现错误提示:

 Reference to generic type 'Dictionary' requires arguments in <...>
Insert '<<#Key: Hashable#>, Any>'

解决办法：
修改为typealias RequestSuccess = (_ success:Dictionary) ->Void即可。

原因

AnyHashable是调和objc和Swift的产物
典型的场景是，objc下无泛型的NSDictionary到了Swift下，会变成什么？（典型例子是苹果来的推送消息）
[Any: Any]，这肯定不对，key必须有hash值，
[AnyObject: Any]，这也不对，同样的AnyObject也未必有hash值
大一统一的理论来了，那就是AnyHashable这个Struct
[AnyHashable: Any] 就是NSDictionary在Swift下的形态。

六、Swift项目中使用AFNetworking

/*
 说明：基础的网络请求设置
 */
import UIKit
import AFNetworking
let ipString = "http://114.114.114.114:74114"
class BaseRequest: NSObject {

    public static func requestManager() ->AFHTTPSessionManager{

        let manager:AFHTTPSessionManager = AFHTTPSessionManager.init()
        manager.requestSerializer = AFJSONRequestSerializer()//请求
        //manager.responseSerializer = AFJSONResponseSerializer()//可以根据服务器类型来选择这个或者下面的
        manager.responseSerializer =  AFHTTPResponseSerializer()//响应

        //TODO:安全连接
        let securityPolicy = AFSecurityPolicy.init()
        securityPolicy.allowInvalidCertificates = true
        manager.securityPolicy = securityPolicy

        //TODO:请求类型
        let netSet:Set = ["application/json",
                                  "text/json",
                                  "text/javascript",
                                  "application/x-json",
                                  "text/html",
                                  "text/plain",
                                  "image/jpg",
                                  "application/json; charset=utf-8",
                                  "multipart/form-data"]
        manager.responseSerializer.acceptableContentTypes = netSet

        //TODO:设置超时
        manager.requestSerializer.willChangeValue(forKey: "timeoutInterval")
        manager.requestSerializer.timeoutInterval = 10.0
        manager.requestSerializer.willChangeValue(forKey: "timeoutInterval")

        return manager
    }
}

import Foundation
import UIKit
import AFNetworking

//MARK: 闭包(block)类型
typealias RequestSuccess = (_ success:NSDictionary) ->Void
typealias RequestFail = (_ fail:Error) ->Void
typealias CancelRequest = () ->Void

/*
 说明：登录模块的请求 
 */
import UIKit
import AFNetworking

class LoginModuleRequest: NSObject {

    public static func requestForUserLogin(_ userName:String,passWord:String,success:@escaping RequestSuccess,fail:@escaping RequestFail) -> URLSessionDataTask{
        let manager:AFHTTPSessionManager = BaseRequest.requestManager()
        let param:[String:String] = ["UserName":userName,"Password":passWord]
        let urlString:String = String.init(format: "%@/Api/Account/Login", ipString)


        let task = manager.post(urlString.addingPercentEncoding(withAllowedCharacters: CharacterSet.urlQueryAllowed)!,
                                parameters: param,
                                progress: nil,
                                success: { (task:URLSessionDataTask!, responseObject:Any!) in
                                    if responseObject != nil{
                                        let dataString =  String.init(data: responseObject as! Data, encoding: String.Encoding.utf8)
                                        let dic = RequestTools.dicFromJson(dataString!) as! NSDictionary
                                        success(dic)
                                    }

        }) { (task:URLSessionDataTask!, error:Error!) in
            if error != nil{ fail(error) }
        }
        return task!
    }
}

后续还会更新....

不足的地方 还请各位多多指教，谢谢了