python睡眠

Hello everyone, hope you are learning python well. In this tutorial we will learn about python time sleep() method. Python sleep function belongs to the python time module that is already discussed earlier

大家好，希望您对python学习得很好。 在本教程中，我们将学习python time sleep（）方法。 Python sleep函数属于前面已经讨论过的python time模块

Python时间睡眠 (Python time sleep)

Python time sleep function is used to add delay in the execution of a program. We can use python sleep function to halt the execution of the program for given time in seconds. Notice that python time sleep function actually stops the execution of current thread only, not the whole program.

Python时间睡眠功能用于增加程序执行的延迟。 我们可以使用python sleep函数在给定的时间（以秒为单位）中暂停程序的执行。 注意，python time sleep函数实际上仅停止当前线程的执行，而不是整个程序的执行。

Python time sleep（）函数语法 (Python time sleep() function syntax)

Python sleep() is a method of python time module. So, first we have to import the time module then we can use this method. Way of using python sleep() function is:

Python sleep（）是python时间模块的一种方法。 因此，首先我们必须导入时间模块，然后才能使用此方法。 使用python sleep（）函数的方式是：

Here the argument of the sleep() method t is in seconds. That means, when the statement time.sleep(t) is executed then the next line of code will be executed after t seconds. See the following example:

这里的sleep（）方法t的参数以秒为单位。 这意味着，当执行语句time.sleep（t）时，下一行代码将在t秒后执行。 请参见以下示例：

# importing time module
import timeprint("Before the sleep statement")
time.sleep(5)
print("After the sleep statement")

If you run the above code then you will see that the second print executes after 5 seconds. So you can make delay in your code as necessary.

如果运行上面的代码，您将看到5秒钟后执行第二次打印。 因此，您可以根据需要延迟代码。

The argument can be in floating value also to have more precise delay. For example you want to make delay for 100 milliseconds which is 0.1 seconds, as following:

该参数可以为浮点值，也可以具有更精确的延迟。 例如，您要延迟100毫秒（即0.1秒），如下所示：

import time
time.sleep(0.100)

Python睡眠示例 (Python sleep example)

Let’s see the following example of python time sleep function.

让我们看下面的python time sleep函数示例。

import time
startTime = time.time()
for i in range(0,5):print(i)# making delay for 1 secondtime.sleep(1)
endTime = time.time()
elapsedTime = endTime - startTime
print("Elapsed Time = %s" % elapsedTime)

This will output:

这将输出：

0
1
2
3
4
Elapsed Time = 5.059988975524902

Elapsed time is greater than 5 because each time in the for loop, execution is halted for 1 second. The extra time is because of the execution time of the program, operating system thread scheduling etc.

经过的时间大于5，因为每次在for循环中，执行都会暂停1秒钟。 额外的时间是由于程序的执行时间，操作系统线程调度等。

python sleep（）的不同延迟时间 (Different delay time of python sleep())

Sometimes you may need to delay for different seconds of time. You can do it as follows:

有时您可能需要延迟不同的时间。 您可以按照以下步骤进行操作：

import timefor i in [ .5, .1, 1, 2]:print("Waiting for %s" % i , end='')print(" seconds")time.sleep(i)

This will output:

这将输出：

Waiting for 0.5 seconds
Waiting for 0.1 seconds
Waiting for 1 seconds
Waiting for 2 seconds

使用sleep（）进行惊人的打印 (Dramatic printing using sleep())

You may need to print some message in a dramatic way, you can do it as following:

您可能需要以戏剧性的方式打印一些消息，可以按照以下步骤进行操作：

# importing time module
import time
message = "Hi!!! I am trying to create suspense"for i in message:# printing each character of the messageprint(i)time.sleep(0.3)

If you run the above code then, you will see that after printing every character of the message it’s taking some time, which seems like dramatic.

如果运行上面的代码，您将看到在打印消息的每个字符之后需要花费一些时间，这似乎很麻烦。

Python线程睡眠 (Python thread sleep)

Python time sleep() function is very important method for multithreading. Below is a simple example showing that the python time sleep function halts the execution of current thread only in multithreaded programming.

Python time sleep（）函数是用于多线程的非常重要的方法。 下面是一个简单的示例，显示python time sleep函数仅在多线程编程中才停止当前线程的执行。

import time
from threading import Threadclass Worker(Thread):def run(self):for x in range(0, 11):print(x)time.sleep(1)class Waiter(Thread):def run(self):for x in range(100, 103):print(x)time.sleep(5)print("Staring Worker Thread")
Worker().start()
print("Starting Waiter Thread")
Waiter().start()
print("Done")

Below image shows the output produced by above python thread sleep example.

下图显示了以上python线程睡眠示例产生的输出。

From the output it’s very clear that only the threads are being stopped from execution and not the whole program by python time sleep function.

从输出中很明显，通过python time sleep函数，只有线程正在停止执行，而不是整个程序。

That’s all about python time sleep function or python sleep function.

这就是关于python time sleep函数或python sleep函数的全部内容。

Reference: StackOverFlow Post, API Doc

参考： StackOverFlow Post ， API文档

翻译自: https://www.journaldev.com/15797/python-time-sleep

python睡眠