1、我们模拟一个网络请求的例子

import java.util.*

fun main(args: Array<String>) {


    var httpUtil=HttpUtil()
    httpUtil.sendRequest("http://www.baidu.com","get",{
        println(it)

    },{
        println(it)
    })

}

/**
 * 模拟发送网络请求
 */
class HttpUtil {
    interface CallBack {
        fun onSuccess(result: String)
        fun onError(e: String)
    }

    fun sendRequest(path: String?, method: String?, onsuccess: ((String) -> Unit)?, onError: ((String) -> Unit)?) {
        println("pth=$path method=$method")
        Thread {
            //创建URL
//            val url = URL(path)
            println("创建URL")

            //打开网络连接
//            val conn = url.openConnection() as HttpURLConnection
            println("打开网络连接")

            //获取响应码
//            val resCode = conn.responseCode

            val code = Random().nextInt(100)
            println("获取响应码")

            if (code % 2 == 0) {
                onsuccess?.invoke("结果正确了")
            } else {
                onError?.invoke("响应码不正确")
            }
        }.start()
    }
}

输出：

image.png

或者

image.png

var httpUtil=HttpUtil()
    httpUtil.sendRequest("http://www.baidu.com","get",{
        println(it)

    },{
        println(it)
    })

想要这样做：更直观

http{
        url="http://www.baidu.com"
        method="get"
        onSuccess{
            println(it)

        }
        onFailed{
            println(it)
        }
    }

修改代码：

import java.util.*

fun main(args: Array<String>) {

    http{
        url="http://www.baidu.com"
        method="get"
        onSuccess{
            println(it)

        }
        onFailer{
            println(it)
        }
    }



}

fun http(block:HttpUtilBuilder.()->Unit)
{
    var httpUtilBuilder=HttpUtilBuilder()
    block.invoke(httpUtilBuilder)
    var httpUtil=HttpUtil()
    httpUtil.sendRequest(httpUtilBuilder.url,httpUtilBuilder.method,httpUtilBuilder.onSuccess,httpUtilBuilder.onFailer)

}

fun HttpUtilBuilder.onSuccess(block: (result:String) -> Unit)
{
    this.onSuccess=block
}

fun HttpUtilBuilder.onFailer(block: (result:String) -> Unit)
{
    this.onFailer=block

}

class HttpUtilBuilder(var url: String?=null, var method: String?=null, var onSuccess: ((String) -> Unit)?=null, var onFailer: ((String) -> Unit)?=null)



/**
 * 模拟发送网络请求
 */
class HttpUtil {
    interface CallBack {
        fun onSuccess(result: String)
        fun onError(e: String)
    }

    fun sendRequest(path: String?, method: String?, onsuccess: ((String) -> Unit)?, onError: ((String) -> Unit)?) {
        println("pth=$path method=$method")
        Thread {
            //创建URL
//            val url = URL(path)
            println("创建URL")

            //打开网络连接
//            val conn = url.openConnection() as HttpURLConnection
            println("打开网络连接")

            //获取响应码
//            val resCode = conn.responseCode

            val code = Random().nextInt(100)
            println("获取响应码")

            if (code % 2 == 0) {
                onsuccess?.invoke("结果正确了")
            } else {
                onError?.invoke("响应码不正确")
            }
        }.start()
    }
}

输出：

image.png