变更

python爬虫/协程.py

@@ -0,0 +1,66 @@
+import asyncio
+import time
+
+
+async def func1():
+    print("hellword")
+    await asyncio.sleep(3)  # await是挂起，异步操作代码
+    print("hellword1")
+
+
+async def func2():
+    print("hellword2")
+    await asyncio.sleep(2)  # await是挂起，异步操作代码
+    print("hellword3")
+
+
+async def func3():
+    print("hellword4")
+    await asyncio.sleep(4)  # await是挂起，异步操作代码
+    print("hellword5")
+
+
+async def main():
+    tasks = [asyncio.create_task(func1()),
+             asyncio.create_task(func2()),
+             asyncio.create_task(func3())]
+    await asyncio.wait(tasks)
+
+
+if __name__ == '__main__':
+    t1 = time.time()
+    asyncio.run(main())
+    t2 = time.time()
+    print(t2 - t1)
+
+# async def func1():
+#     print("hellword")
+#     # time.sleep(3)  # 出现同步操作时候，异步会中断
+#     await asyncio.sleep(3)# await是挂起，异步操作代码
+#     print("hellword1")
+#
+#
+# async def func2():
+#     print("hellword2")
+#     # time.sleep(2)
+#     await asyncio.sleep(2)# await是挂起，异步操作代码
+#     print("hellword3")
+#
+#
+# async def func3():
+#     print("hellword4")
+#     # time.sleep(4)
+#     await asyncio.sleep(4)# await是挂起，异步操作代码
+#     print("hellword5")
+
+
+# if __name__ == '__main__':
+#     f1 = func1()
+#     f2 = func2()
+#     f3 = func3()
+#     t1 = time.time()3
+#     tasks = [f1, f2, f3]
+#     # 一次启动多个任务
+#     asyncio.run(asyncio.wait(tasks))
+#     t2 = time.time()
+#     print(t2-t1)