如何在python中判断变量的类型

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python的数据类型有：数字(int)、浮点(float)、字符串(str)，列表(list)、元组(tuple)、字典(dict)、集合(set)

一般通过以下方法进行判断：

1、isinstance(参数1,参数2)

描述：该函数用来判断一个变量（参数1）是否是已知的变量类型(参数2) 类似于type()

参数1：变量

参数2：可以是直接或间接类名、基本类型或者由它们组成的元组。

返回值: 如果对象的类型与参数二的类型（classinfo）相同则返回 True，否则返回 False

例子:

#判断变量类型的函数
def typeof(variate):
  type=None
  if isinstance(variate,int):
    type = "int"
  elif isinstance(variate,str):
    type = "str"
  elif isinstance(variate,float):
    type = "float"
  elif isinstance(variate,list):
    type = "list"
  elif isinstance(variate,tuple):
    type = "tuple"
  elif isinstance(variate,dict):
    type = "dict"
  elif isinstance(variate,set):
    type = "set"
  return type
# 返回变量类型
def getType(variate):
  arr = {"int":"整数","float":"浮点","str":"字符串","list":"列表","tuple":"元组","dict":"字典","set":"集合"}
  vartype = typeof(variate)
  if not (vartype in arr):
    return "未知类型"
  return arr[vartype]

#判断变量是否为整数
money=120
print("{0}是{1}".format(money,getType(money)))
#判断变量是否为字符串
money="120"
print("{0}是{1}".format(money,getType(money)))
money=12.3
print("{0}是{1}".format(money,getType(money)))
#判断变量是否为列表
students=['studentA']
print("{0}是{1}".format(students,getType(students)))
#判断变量是否为元组
students=('studentA','studentB')
print("{0}是{1}".format(students,getType(students)))
#判断变量是否为字典
dictory={"key1":"value1","key2":"value2"}
print("{0}是{1}".format(dictory,getType(dictory)))
#判断变量是否为集合
apple={"apple1","apple2"}46 print("{0}是{1}".format(apple,getType(apple)))

2、通过与已知类型的常量进行比较

例子：

#判断变量类型的函数
def typeof(variate):
  type1 = ""
  if type(variate) == type(1):
    type1 = "int"
  elif type(variate) == type("str"):
    type1 = "str"
  elif type(variate) == type(12.3):
    type1 = "float"
  elif type(variate) == type([1]):
    type1 = "list"
  elif type(variate) == type(()):
    type1 = "tuple"
  elif type(variate) == type({"key1":"123"}):
    type1 = "dict"
  elif type(variate) == type({"key1"}):
    type1 = "set"
  return type1
# 返回变量类型
def getType(variate):
  arr = {"int":"整数","float":"浮点","str":"字符串","list":"列表","tuple":"元组","dict":"字典","set":"集合"}
  vartype = typeof(variate)
  if not (vartype in arr):
    return "未知类型"
  return arr[vartype]

#判断变量是否为整数
money=120
print("{0}是{1}".format(money,getType(money)))
#判断变量是否为字符串
money="120"
print("{0}是{1}".format(money,getType(money)))
money=12.3
print("{0}是{1}".format(money,getType(money)))
#判断变量是否为列表
students=['studentA']
print("{0}是{1}".format(students,getType(students)))
#判断变量是否为元组
students=('studentA','studentB')
print("{0}是{1}".format(students,getType(students)))
#判断变量是否为字典
dictory={"key1":"value1","key2":"value2"}
print("{0}是{1}".format(dictory,getType(dictory)))
#判断变量是否为集合
apple={"apple1","apple2"}
print("{0}是{1}".format(apple,getType(apple)))