Question

在我的一个应用程序中，我使用了块来进行webservice调用并获得响应。现在我想在swift中编写这个应用程序，但是我在Swift中使用blocks / Closure时遇到了麻烦。这是我想要在swift中迁移的客观C代码：

调用Communicator的类方法

[[Communicator sharedInstance]callWebService:WS_LOGIN withMethod:POST_METHOD andParams:params showLoader:YES completionBlockSuccess:^(id obj) {
   //Do play with data
}completionBlockFailiure:^(id obj) {
   //Show alert with error
}];

在沟通者班级

-(void)callWebService:(NSString *)serviceName withMethod:(NSString *)methodName andParams:(NSDictionary *)params showLoader:(BOOL)showLoader completionBlockSuccess:(void (^)(id))aBlock completionBlockFailiure:(void (^)(id))aFailBlock
{
   if (showLoader) {
   // show loader
   }
   [self performRequestWithServiceName:serviceName method:methodName andParams:params successblock:aBlock failureblock:aFailBlock];
}

- (void)performRequestWithServiceName:(NSString *)serviceName method:(NSString*)methodName andParams:(NSDictionary*)params
                 successblock:(void (^)(id obj))successBlock
                 failureblock:(void (^)(id obj))failBlock {
   if(callSuceess){
      successBlock(@"Success");
   }else{
      successBlock(nil);
   }
}

Answer 1

对于斯威夫特。将AnyObject用于id objc类型。

func callWebservice (serviceName: String, withMethod method: String, andParams params: NSDictionary, showLoader loader: Bool, completionBlockSuccess aBlock: ((AnyObject) -> Void), andFailureBlock failBlock: ((AnyObject) -> Void)) {
    if loader {
        // Show loader
    }

    performRequestWithServiceName(serviceName, method: method, andParams: params, success: aBlock, failure: failBlock)
}

func performRequestWithServiceName(serviceName: String, method methodName: String, andParams params: NSDictionary, success successBlock: ((AnyObject) -> Void), failure failureBlock: ((AnyObject) -> Void)) {
    if callSuceess {
        successBlock("Success")
    }else {
        successBlock(nil)
    }
}

更新：您需要致电web service的示例。见下面的代码

callWebservice("your-service-name", withMethod: "your-method", andParams: ["your-dic-key": "your dict value"], showLoader: true/*or false*/, completionBlockSuccess: { (success) -> Void in
    // your successful handle
}) { (failure) -> Void in
    // your failure handle
}

Answer 2

您的代码可能如下所示：

func callWebService(serviceName: String, method: String, params: [String : AnyObject], showLoader: Bool, success: (responseObject: AnyObject) -> Void, failure: (responseObject: AnyObject) -> Void) {
    if showLoader {
        // show loader
    }

    performRequest(serviceName, method: method, params: params, success: success, failure: failure)
}

func performRequest(serviceName: String, method: String, params: [String : AnyObject], success: (responseObject: AnyObject) -> Void, failure: (responseObject: AnyObject) -> Void) {

}

我将NSDictionary替换为[String : AnyObject]。如果您可以用更具体的类型替换AnyObject的任何用途，那么您的代码将更清晰，更稳定。

Answer 3

对于Swift Closures，我们必须使用( ) -> ( )

例如：

func yourFunction(success: (response: AnyObject!) -> Void, failure: (error: NSError?) -> Void) {

}

您可以将其命名为：

yourFunction({(response) -> Void in
    // Success
}) { (error) -> Void in
    // Handle Errors
}

希望它能帮助您根据自己的要求创建Closures。

Answer 4

在communicator类中，根据你想要返回的对象类型，定义web服务的方法将被定义为类似

func performRequest(serviceName: NSString, methodName: NSString,paramaters:NSDictionary, successblock: (String)->(), failureBlock: () -> ()) {
    if(callSuccess) {
        successblock("Success")
    } else {
       failureBlock() 
}

我们通过函数签名定义成功和失败块类型，在上面的情况下，成功被定义为一个方法，它将字符串作为输入参数并且不返回任何内容，因此我们可以调用successBlock传入字符串。上面将故障块定义为不带参数且不返回任何内容的块。

调用此方法

func callWebService(serviceName: NSString, method: NSString and parameters: NSDictionary, showLoader: Bool, completionBlockSuccess:(String) -> (), completionBlockFailiure:() -> ()) {
    if (showLoader) {
    // show loader
    }
    performRequest(serviceName: serviceName, methodName: method, parameters, successBlock:completionBlockSuccess, failureBlock: completionBlockFailiure)
}

最后称之为

Communicator.sharedInstance().callWebService(serviceName: WS_LOGIN , method: POST_METHOD and parameters: params, showLoader: true, completionBlockSuccess:{ returnedString in

     //Do play with data

}, completionBlockFailiure:{ 

    //Show alert with error

})

对于完成块，我们定义一个变量returnedString，以允许我们操作该输入参数（在上面的例子中，它将是字符串“Success”）。我假设你的数据不只是返回一个字符串，所以你可能需要根据你的服务返回来打字。

此外，我尝试使用NSString和NSDictionary匹配您的方法签名，但根据您的需要，Swift等效String和[String：AnyObject]可能更合适。

Answer 5

func processingWithAnyObject(input: String, completion: @escaping (_ result: AnyObject) -> Void) {
    ...
    completion(response.result.value! as AnyObject)
}

processingWithAnyObject("inputString") {
    (result: AnyObject) in
    print("back to caller: \(result)")
}

如何在swift中使用块/闭包

调用Communicator的类方法

在沟通者班级

5 个答案: