Swift 3.0使用URLSession写一个网络请求类

一个hearder,一个httpBody,加上dataTask方法就能搞定,和几个处理请求参数的函数,下面上代码

类方法写的请求方法,参数,闭包

 static func request(method: String, url: String, params: Dictionary = Dictionary(), callback: @escaping (_ data: NSData?, _ response: URLResponse?, _ error: NSError?) -> Void) {
        let session = URLSession.shared
        
        var newURL = url
        if method == "GET" {
            newURL += "?" + Network().buildParams(params)
        }
        
        let request = NSMutableURLRequest(url: NSURL(string: newURL)! as URL)
        request.httpMethod = method
        
        
        
        if method == "POST" {
            request.addValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
            request.httpBody = Network().buildParams(params).data(using: String.Encoding.utf8)
        }
        
        
        
        let task = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
            callback(data as NSData?, response , error as NSError?)
        })
        task.resume()
    }
    

处理参数的方法:

    //请求体,并处理特殊字符串 !$&'()*+,;= :#[]@
    private func buildParams(_ parameters: [String: Any]) -> String {
        var components: [(String, String)] = []
        
        for key in parameters.keys.sorted(by: <) {
            let value = parameters[key]!
            components += queryComponents(fromKey: key, value: value)
        }
        
        return components.map { "\($0)=\($1)" }.joined(separator: "&")
    }
    
    public func queryComponents(fromKey key: String, value: Any) -> [(String, String)] {
        var components: [(String, String)] = []
        
        if let dictionary = value as? [String: Any] {
            for (nestedKey, value) in dictionary {
                components += queryComponents(fromKey: "\(key)[\(nestedKey)]", value: value)
            }
        } else if let array = value as? [Any] {
            for value in array {
                components += queryComponents(fromKey: "\(key)[]", value: value)
            }
        } else if let value = value as? NSNumber {
            if value.isBool {
                components.append((escape(key), escape((value.boolValue ? "1" : "0"))))
            } else {
                components.append((escape(key), escape("\(value)")))
            }
        } else if let bool = value as? Bool {
            components.append((escape(key), escape((bool ? "1" : "0"))))
        } else {
            components.append((escape(key), escape("\(value)")))
        }
        
        return components
    }
    
    
    
    public func escape(_ string: String) -> String {
        let generalDelimitersToEncode = ":#[]@" // does not include "?" or "/" due to RFC 3986 - Section 3.4
        let subDelimitersToEncode = "!$&'()*+,;="
        
        var allowedCharacterSet = CharacterSet.urlQueryAllowed
        allowedCharacterSet.remove(charactersIn: "\(generalDelimitersToEncode)\(subDelimitersToEncode)")
        
        return string.addingPercentEncoding(withAllowedCharacters: allowedCharacterSet) ?? string
    }

外面加一个NSNumber的扩展

extension NSNumber {
    fileprivate var isBool: Bool { return CFBooleanGetTypeID() == CFGetTypeID(self) }
}