String conversion

Character divided, int integer str string bool Boolean

Three types can be converted to each other, but can only convert convertible

String

• After use character formatting, it will generate a new value, the old value of the variable constant.

• Variable .uppre () converts uppercase

  • The variable string unified capitalized.

• Variable .lower () converts lowercase

  • The variable string unified lowercase.

• Mainly for the user to enter a default case are correct. For example codes, not case-sensitive.

  value = "adck WB"
  new_value = value.upper()  # 这里使用转换后，会生成一个新的变量，老变量不变。
  new_value1 = value.lower() #所有字符转换成小写
  print(new_value,new_value1)

• Variable .isbigit () determines whether the digital

  • Determining whether the string input by the user can be converted into digital. No to False for Ttrue

• Variable .strip () to space

  • Remove the space character on both sides. User input mainly used to eliminate extra spaces on both sides, prevent errors.
  • Variable .lstrip () to remove the character to the left spaces.
  • Variable .rstrip () to remove the character to the left spaces.

  # ####### .strip/.rstrip/.lstrip 去两边空格/去左空格/去右空格  .isdigit 判断是否为数字 #######
  content = input('请输入数字编号：')
  new_content = content.strip()  #去除输入的字符串两边的空格。防止用户出错
  print(content,'<-这是原输入->这是去空格后',new_content)
  if new_content.isdigit():     #判断输入的字符串是否为数字。
      print(new_content,'输入正确')
  else:
      print(new_content,'请输入纯数字，且中间不能有空格')

• Variable .replace () replacement

  • Keyword substitution

  # #######.replace 替换 #######
  message = input('请输入发布你的信息：')
  new_message = message.replace('台独','**',2) # 要替换的字符，替换为，替换几个
  print(new_message)

• Segmentation variable .split

  • The character segmentation

  # #######.split/lsplit/.rsplit 切割/左分割/右分割 #######
  message = "我今天学习，学习如何。使用切割，但是还不。太懂。我今天学习，学习如何使用切割，但是还不太懂。"
  mage = message.split('。',2) # 将字符串分割。（以什么为分割点，分割成几部分）
  print(mage)