package com.tiger.mykotlinapp.scope
import kotlinx.coroutines.CoroutineStart
import kotlinx.coroutines.async
import kotlinx.coroutines.delay
import kotlinx.coroutines.runBlocking
fun main():Unit = runBlocking {
    val d = async(start = CoroutineStart.LAZY){
        test()
    }
    println("hello")
    println("hello")
    println("hello")
    println("hello")
    println("hello")
    println("hello")
    println("hello")
    println(d.await())//代表开启线程执行, 拿到返回值
}
suspend fun test():Int{
    println("执行中")
    delay(1000)
    return 100
}

package com.tiger.mykotlinapp.scope
import kotlinx.coroutines.CoroutineStart
import kotlinx.coroutines.async
import kotlinx.coroutines.delay
import kotlinx.coroutines.runBlocking
import kotlinx.coroutines.selects.select
fun main():Unit = runBlocking {
    val d = async(start = CoroutineStart.LAZY){
        test1("1")
    }
    val c = async(start = CoroutineStart.LAZY){
        delay(2000)
        test1("2")
    }
    println(select {
        //阻塞主线程把协程等待结束再继续执行 谁先执行完毕，就退出返回先结束的那个返回值
        c.onAwait.invoke {
            it
        }
        d.onAwait.invoke {
            it
        }
    })
    println("end")
//    println(d.await())//代表开启线程执行, 拿到返回值
}
suspend fun test1(a:String):String{
    println("执行中$a")
    delay(1000)
    return a
}

package com.tiger.mykotlinapp.scope
import kotlinx.coroutines.CoroutineStart
import kotlinx.coroutines.async
import kotlinx.coroutines.delay
import kotlinx.coroutines.runBlocking
import kotlinx.coroutines.selects.select
fun main():Unit = runBlocking {
    val d = async(start = CoroutineStart.LAZY){
        test3("1")
    }
    val c = async(start = CoroutineStart.LAZY){
        delay(2000)
        test3("2")
    }
    println(select {
        //阻塞主线程把协程等待结束再继续执行 谁先执行完毕，就退出返回先结束的那个返回值
        c.onAwait.invoke {
            it
        }
        d.onAwait.invoke {
            it
        }
    })
    println("end")
//    println(d.await())//代表开启线程执行, 拿到返回值
}
suspend fun test3(a:String):String{
    println("执行中$a")
    delay(1000)
    return a
}

getCompleted

这个是立刻获取协程异步执行的值

如果还没执行完毕就抛异常