如何在python中判斷變量的類型

更新時間：2020年07月29日 10:40:43 作者：小銘博客

這篇文章主要介紹了如何在python中判斷變量的類型，文中講解非常細(xì)致，代碼幫助大家更好的理解和學(xué)習(xí)，感興趣的朋友可以了解下

python的數(shù)據(jù)類型有：數(shù)字(int)、浮點(float)、字符串(str)，列表(list)、元組(tuple)、字典(dict)、集合(set)

一般通過以下方法進(jìn)行判斷：

1、isinstance(參數(shù)1,參數(shù)2)

描述：該函數(shù)用來判斷一個變量（參數(shù)1）是否是已知的變量類型(參數(shù)2) 類似于type()

參數(shù)1：變量

參數(shù)2：可以是直接或間接類名、基本類型或者由它們組成的元組。

返回值: 如果對象的類型與參數(shù)二的類型（classinfo）相同則返回 True，否則返回 False

例子:

#判斷變量類型的函數(shù)
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
# 返回變量類型
def getType(variate):
  arr = {"int":"整數(shù)","float":"浮點","str":"字符串","list":"列表","tuple":"元組","dict":"字典","set":"集合"}
  vartype = typeof(variate)
  if not (vartype in arr):
    return "未知類型"
  return arr[vartype]

#判斷變量是否為整數(shù)
money=120
print("{0}是{1}".format(money,getType(money)))
#判斷變量是否為字符串
money="120"
print("{0}是{1}".format(money,getType(money)))
money=12.3
print("{0}是{1}".format(money,getType(money)))
#判斷變量是否為列表
students=['studentA']
print("{0}是{1}".format(students,getType(students)))
#判斷變量是否為元組
students=('studentA','studentB')
print("{0}是{1}".format(students,getType(students)))
#判斷變量是否為字典
dictory={"key1":"value1","key2":"value2"}
print("{0}是{1}".format(dictory,getType(dictory)))
#判斷變量是否為集合
apple={"apple1","apple2"}46 print("{0}是{1}".format(apple,getType(apple)))

返回:

2、通過與已知類型的常量進(jìn)行比較

例子：

#判斷變量類型的函數(shù)
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
# 返回變量類型
def getType(variate):
  arr = {"int":"整數(shù)","float":"浮點","str":"字符串","list":"列表","tuple":"元組","dict":"字典","set":"集合"}
  vartype = typeof(variate)
  if not (vartype in arr):
    return "未知類型"
  return arr[vartype]

#判斷變量是否為整數(shù)
money=120
print("{0}是{1}".format(money,getType(money)))
#判斷變量是否為字符串
money="120"
print("{0}是{1}".format(money,getType(money)))
money=12.3
print("{0}是{1}".format(money,getType(money)))
#判斷變量是否為列表
students=['studentA']
print("{0}是{1}".format(students,getType(students)))
#判斷變量是否為元組
students=('studentA','studentB')
print("{0}是{1}".format(students,getType(students)))
#判斷變量是否為字典
dictory={"key1":"value1","key2":"value2"}
print("{0}是{1}".format(dictory,getType(dictory)))
#判斷變量是否為集合
apple={"apple1","apple2"}
print("{0}是{1}".format(apple,getType(apple)))

返回: