Python 上限法不适用于'；没有道理

代码：

def solve_the_input(port):
    port = hex(int(port))
    split_result = port.split("0x")
    split_port = split_result[1]
    print 'input port is ',split_port
    split_port.upper()
    print 'input port is ',split_port
    return split_port

if __name__ == "__main__":
    if len(sys.argv) == 1:
        print "please input a port"
    else:
        port = solve_the_input(sys.argv[1])

input port is  a558
input port is  a558

input port is  a558
input port is  A558

输入

python test.py 42328

实际产出：

def solve_the_input(port):
    port = hex(int(port))
    split_result = port.split("0x")
    split_port = split_result[1]
    print 'input port is ',split_port
    split_port.upper()
    print 'input port is ',split_port
    return split_port

if __name__ == "__main__":
    if len(sys.argv) == 1:
        print "please input a port"
    else:
        port = solve_the_input(sys.argv[1])

input port is  a558
input port is  a558

input port is  a558
input port is  A558

预期产出：

def solve_the_input(port):
    port = hex(int(port))
    split_result = port.split("0x")
    split_port = split_result[1]
    print 'input port is ',split_port
    split_port.upper()
    print 'input port is ',split_port
    return split_port

if __name__ == "__main__":
    if len(sys.argv) == 1:
        print "please input a port"
    else:
        port = solve_the_input(sys.argv[1])

input port is  a558
input port is  a558

input port is  a558
input port is  A558

我不知道为什么upper（）方法不能按预期工作。

upper方法返回新的大写字符串。所以使用

split_port = split_result[1].upper()

upper方法以大写形式返回新字符串。所以使用

split_port = split_result[1].upper()

几点

• split\u port.upper（）

  return未分配回

  split\u port

• 无需在

  '0x'

  上拆分。您可以改用

  replace

  功能。就不会那么复杂了

带有替换功能的代码：

import sys
def solve_the_input(port):
    port = hex(int(port))
    result = port.replace("0x",'')
    print 'input port is ',result
    result = result.upper()
    print 'input port is ',result
    return result

if __name__ == "__main__":
   if len(sys.argv) == 1:
       print "please input a port"
   else :
       port = solve_the_input(sys.argv[1])

C:\Users\dinesh_pundkar\Desktop>python c.py 1235
input port is  4d3
input port is  4D3

C:\Users\dinesh_pundkar\Desktop>

输出：

import sys
def solve_the_input(port):
    port = hex(int(port))
    result = port.replace("0x",'')
    print 'input port is ',result
    result = result.upper()
    print 'input port is ',result
    return result

if __name__ == "__main__":
   if len(sys.argv) == 1:
       print "please input a port"
   else :
       port = solve_the_input(sys.argv[1])

C:\Users\dinesh_pundkar\Desktop>python c.py 1235
input port is  4d3
input port is  4D3

C:\Users\dinesh_pundkar\Desktop>

几点

• split\u port.upper（）

  return未分配回

  split\u port

• 无需在

  '0x'

  上拆分。您可以改用

  replace

  功能。就不会那么复杂了

带有替换功能的代码：

import sys
def solve_the_input(port):
    port = hex(int(port))
    result = port.replace("0x",'')
    print 'input port is ',result
    result = result.upper()
    print 'input port is ',result
    return result

if __name__ == "__main__":
   if len(sys.argv) == 1:
       print "please input a port"
   else :
       port = solve_the_input(sys.argv[1])

C:\Users\dinesh_pundkar\Desktop>python c.py 1235
input port is  4d3
input port is  4D3

C:\Users\dinesh_pundkar\Desktop>

输出：

import sys
def solve_the_input(port):
    port = hex(int(port))
    result = port.replace("0x",'')
    print 'input port is ',result
    result = result.upper()
    print 'input port is ',result
    return result

if __name__ == "__main__":
   if len(sys.argv) == 1:
       print "please input a port"
   else :
       port = solve_the_input(sys.argv[1])

C:\Users\dinesh_pundkar\Desktop>python c.py 1235
input port is  4d3
input port is  4D3

C:\Users\dinesh_pundkar\Desktop>

---

返回新字符串的上限方法，但需要存储该字符串

split_port = split_result[1].upper()

---

返回新字符串的上限方法，但需要存储该字符串

split_port = split_result[1].upper()

---

python的基本规则：字符串方法不改变字符串-它们不能改变，因为字符串是不可变的（只读的）-所以它们总是返回一个新的字符串对象。python的基本规则：字符串方法不改变字符串-它们不能改变，因为字符串是不可变的（只读的）-所以它们总是返回一个新的字符串对象。