print()函数是Python中的库函数,用于将给定参数(对象)的值打印到标准输出流,即在屏幕上打印。
通用语法:
print(text/object)
完整语法:
print(objects, sep=' ', end='\n', file=sys.stdout, flush=False)
Parameter(s):
objects:要在屏幕上打印的值或变量/对象,可以通过逗号分隔多个对象(object1,object2,...,objectN)。
sep:这是一个可选参数,用于指定参数之间的分隔符,默认值为空格('')。
阅读更多:print()函数中的sep参数。
end:它也是一个可选参数,用于指定最后要打印的值。默认值为换行符('\ n')。
阅读更多:print()函数中的结束参数。
file:它也是一个可选参数,用于指定我们可以在其中写入参数值的文件名。默认值为sys.stdout。
阅读更多:print()函数中的文件参数。
flush:它也是可选参数,用于刷新流。默认值为“ False”。
阅读更多:print()函数中的flush参数。
返回值:
print()函数的返回类型为NoneType,不返回任何内容。
示例1:打印文本,值等(即不使用可选参数)
# Python代码演示示例
# 不使用print()函数
# 可选参数
# 打印字符串
print("Hello, world!")
print("How are you?")
print("India","USA", "Russia", "Israel")
print()
# 印刷混合价值
print("Mike", 21, "USA", 65.50)
print([10, 20, 30]) # 清单
print({"Mike", 21, "USA", 123.5}) # 组
print(123, "Hello", [10, 20, 30]) #数字,字符串,列表
print()
# 打印文本或/和变量
name = "Mike"
age = 21
con = "USA"
w = 65.50
print(name, age, con, w)
print("Name:", name, "Age:", age, "Country:", con, "Weight:", w)输出:
Hello, world!
How are you?
India USA Russia Israel
Mike 21 USA 65.5
[10, 20, 30]
{'Mike', 123.5, 'USA', 21}
123 Hello [10, 20, 30]
Mike 21 USA 65.5
Name: Mike Age: 21 Country: USA Weight: 65.5示例2: print()使用sep参数
# Python代码演示示例
# 带有sep参数的print()函数
print("Separated by ','")
print("Mike", 21, "USA", 65.50, sep=',')
print("Separated by ' # '")
print("Mike", 21, "USA", 65.50, sep=' # ')
print()
name = "Mike"
age = 21
con = "USA"
w = 65.50
print("Separated by ','")
print(name, age, con, w, sep=',')
print("Separated by '\n'")
print("Name:", name, "Age:", age, "Country:", con, "Weight:", w, sep='\n')输出:
Separated by ',' Mike,21,USA,65.5 Separated by ' # ' Mike # 21 # USA # 65.5 Separated by ',' Mike,21,USA,65.5 Separated by ' ' Name: Mike Age: 21 Country: USA Weight: 65.5
示例3: print()带有结束参数
# Python代码演示示例
# 带有结束参数的print()函数
print("Ended by none i.e. removing default sep value")
print("Hello,", end='')
print("world", end='')
print("Ended by '###\\n'")
print("Mike", 21, "USA", 65.50, end='###\n')
print("Ended by '-END-\\n'")
print("Mike", 21, "USA", 65.50, end='-END-\n')
print()
name = "Mike"
age = 21
con = "USA"
w = 65.50
print("Ended by 'FINISH\\n'")
print(name, age, con, w, end='FINISH\n')
print("Ended by '@@@@'")
print("Name:", name, "Age:", age, "Country:", con, "Weight:", w, end='@@@')输出:
Ended by none i.e. removing default sep value Hello,worldEnded by '###\n' Mike 21 USA 65.5### Ended by '-END-\n' Mike 21 USA 65.5-END- Ended by 'FINISH\n' Mike 21 USA 65.5FINISH Ended by '@@@@' Name: Mike Age: 21 Country: USA Weight: [email protected]@@
示例4: print()带有文件参数
# Python代码演示示例
# 带文件参数的print()函数
import sys
print("Printing to sys.stderr")
print("Hello, world!", file = sys.stderr)
print("Printing to an external file")
objF = open("logs.txt", "w")
print("How are you?", file = objF)
objF.close()输出:
Printing to sys.stderr Hello, world! Printing to an external file ---logs.txt--- How are you?
示例5: print()带有flush参数
# Python代码演示示例
# 带冲洗参数的print()函数
from time import sleep
# 输出在这里刷新
print("Hello, world!", end='', flush= True)
sleep(5)
print("Bye!!!")
# 在这里不刷新输出
print("NHOOO", end='')
sleep(5)
print("Okay!!!")输出:
Hello, world!Bye!!! NHOOOOkay!!!
看到输出–“你好,世界”和“再见!!!” 之所以正确打印,是因为在sleep(5)之前,它print()正在冲洗,但是显示“ NHOOO”和“好!!!” 正在一起打印,因为print()没有冲洗。