字符串转换整数python_将Python字符串转换为Int：如何在Python中将字符串转换为整数

参考链接： 在Python中将整数int转换为字符串string

字符串转换整数python

 Unlike many other programming languages out there, Python does not implicitly typecast integers (or floats) to strings when you concatenate them to strings.

  与现有的许多其他编程语言不同，Python在将整数连接到字符串时不会隐式地将整数(或浮点数)类型转换为字符串。  

 Fortunately, Python has a handy built-in function str() which will convert the argument passed in to a string format.

  幸运的是，Python有一个方便的内置函数str() ，它将把传入的参数转换为字符串格式。  

  在Python中将字符串转换为整数的错误方法 (The Wrong Way to Convert a String to an Integer in Python) 

 Programmers coming from other programming languages may attempt to do the following string concatenation, which will produce an error:

  来自其他编程语言的程序员可能会尝试执行以下字符串连接，这将产生错误：  

 age = 18

string = "Hello, I am " + age + " years old"

 You can run this code on repl.it.

  您可以在repl.it上运行此代码 。  

 The error that shows up is:

  显示的错误是：  

 Traceback (most recent call last):

  File "python", line 3, in <module>

TypeError: must be str, not int

 Here, TypeError: must be str, not int indicates that the integer must first be converted to a string before it can be concatenated.

  在这里， TypeError: must be str, not int ，该整数必须先转换为字符串才能连接。  

  在Python中将字符串转换为整数的正确方法 (The Correct Way to Convert a String to an Integer in Python ) 

 Here's a simple concatenation example:

  这是一个简单的串联示例：  

 age = 18

print("Hello, I am " + str(age) + " years old")

# Output

# Hello, I am 18 years old

 You can run this code on repl.it.

  您可以在repl.it上运行此代码 。  

 Here's how to print 1 2 3 4 5 6 7 8 9 10 using a single string:

  以下是使用单个字符串打印1 2 3 4 5 6 7 8 9 10方法：  

 result = ""

for i in range(1, 11):

    result += str(i) + " "

print(result)

# Output

# 1 2 3 4 5 6 7 8 9 10

 You can run the code on repl.it.

  您可以在repl.it上运行代码 。  

  以下是上述代码的工作原理的逐行说明： (Here's a line-by-Line explanation of how the above code works:) 

 First of all a variable ‘result’ is assigned to an empty string. 首先，将变量“结果”分配给一个空字符串。 The for loop is being used to iterate over a list of numbers. for循环用于遍历数字列表。 This list of numbers is generated using the range function. 此数字列表是使用范围函数生成的。 so range(1,11) is going to generate a list of numbers from 1 to 10. 因此range(1,11)将生成一个从1到10的数字列表。 On each for loop iteration this ‘i’ variable is going to take up values from 1 to 10. 在每个for循环迭代中，此“ i”变量将采用从1到10的值。 On first iteration when the variable i=1,then the variable [result=result+str(i)+“(space character)”],str(i) converts the ‘i’ which is an integer value to a string value. 在第一次迭代中，当变量i = 1时，然后变量[result = result + str(i)+“(space character)”]，str(i)将整数值“ i”转换为字符串值。 Since i=1, on the first iteration finally result=1. 由于i = 1，因此在第一次迭代中最终结果= 1。 And the same process goes on until i=10 and finally after the last iteration result=1 2 3 4 5 6 7 8 9 10. 直到i = 10，最后一次迭代结果= 1 2 3 4 5 6 7 8 9 10。 Therefore when we finally print the result after the for loop the output on the console is ‘1 2 3 4 5 6 7 8 9 10’. 因此，当我们最终在for循环之后打印结果时，控制台上的输出为'1 2 3 4 5 6 7 8 9 10'。 

 I hope you've found this helpful. Happy coding. 

  希望对您有所帮助。 快乐的编码。  

  翻译自: https://www.freecodecamp.org/news/python-string-to-int-how-to-convert-a-string-to-an-integer-in-python/

 字符串转换整数python