python基礎(chǔ)知識(shí)之字典(Dict)
更新時(shí)間：2023年02月19日 09:36:26 作者：51碼銀
這篇文章主要介紹了python基礎(chǔ)知識(shí)之字典(Dict)的相關(guān)資料,需要的朋友可以參考下
一、字典的基本操作
1.定義字典
字典也是一個(gè)列表型的數(shù)據(jù)結(jié)構(gòu)，字典的數(shù)據(jù)是用“{ }”裝的（列表：[ ]，元組：( )），字典的元素是一一對(duì)應(yīng)的關(guān)系“key-value”。
格式：
Dictname={ key1:value1,...,key2:value2}
#value是任何的python的對(duì)象
#字典的元素?cái)?shù)量也是用len()函數(shù)
多說(shuō)無(wú)益，直接看例子比較清晰：
實(shí)例：
flower={'rose':10,'orchid':16,'carnation':8}
tea={'紅茶':30,'綠茶':20,'茉莉花茶':40}
print(flower)
print(tea)
print("字典flower的元素?cái)?shù)量是：",len(flower))
print("字典的數(shù)據(jù)類型：",type(tea))
2.建立空字典
實(shí)例：
print("``````````````````````````````````````````````````````````")
flower={}
flower['rose']=13
flower['orchid']=16
print(flower)
print("``````````````````````````````````````````````````````````")
3.列出字典元素的值
格式：
flower【'rose'】
#注意列出字典元素的值要用中括號(hào)哦“[ ]”
#上面語(yǔ)句表達(dá)的意思是字典 flower 的 rose（key）的對(duì)應(yīng) 10（value）值。
實(shí)例：
print("``````````````````````````````````````````````````````````")
flower={'rose':10,'orchid':16,'carnation':8}
tea={'紅茶':30,'綠茶':20,'茉莉花茶':40}
print("一支玫瑰的價(jià)錢是：",flower['rose'])
print("紅茶一袋的價(jià)錢是：",tea['紅茶'])
print("``````````````````````````````````````````````````````````")
如果有兩個(gè)“rose”，兩個(gè)“紅茶”呢，元素對(duì)應(yīng)的值（value）是哪個(gè)呢？
print("``````````````````````````````````````````````````````````")
flower={'rose':10,'orchid':16,'carnation':8,'rose':15}
tea={'紅茶':30,'綠茶':20,'茉莉花茶':40,'紅茶':13}
print("一支玫瑰的價(jià)錢是：",flower['rose'])
print("紅茶一袋的價(jià)錢是：",tea['紅茶'])
print("``````````````````````````````````````````````````````````")
如上所示，字典中的元素對(duì)應(yīng)值被后面的值占領(lǐng)了。
4.增加字典元素
實(shí)例：
print("``````````````````````````````````````````````````````````")
flower={'rose':10,'orchid':16,'carnation':8}
tea={'紅茶':30,'綠茶':20,'茉莉花茶':40}
flower['tuilp']=13
print(flower)
print("``````````````````````````````````````````````````````````")
5.更改元素內(nèi)容
實(shí)例：
print("``````````````````````````````````````````````````````````")
flower={'rose':10,'orchid':16,'carnation':8}
tea={'紅茶':30,'綠茶':20,'茉莉花茶':40}
flower['rose']=13
print(flower)
print("``````````````````````````````````````````````````````````")
6.刪除字典（特定元素）
刪除元素實(shí)例：
print("``````````````````````````````````````````````````````````")
flower={'rose':10,'orchid':16,'carnation':8}
tea={'紅茶':30,'綠茶':20,'茉莉花茶':40}
del flower['rose']
print(flower)
print("``````````````````````````````````````````````````````````")
刪除字典實(shí)例：
print("``````````````````````````````````````````````````````````")
flower={'rose':10,'orchid':16,'carnation':8}
del flower
print(flower)
print("``````````````````````````````````````````````````````````")
7. 字典的復(fù)制
print("``````````````````````````````````````````````````````````")
flower={'rose':10,'orchid':16,'carnation':8}
copyflower=flower.copy()
print(flower)
print(copyflower)
print("``````````````````````````````````````````````````````````")
二、遍歷字典
1.遍歷字典的key-value
flower={'rose':10,
'orchid':16,
'carnation':8}
for flowers,price in flower.items():
print("花名：",flowers)
print("價(jià)格：",price)
print("\n")
2.遍歷字典的鍵(key)
flower={'rose':10,
'orchid':16,
'carnation':8}
for flowers in flower.keys():
print("花名：",flowers)
print("\n")
沒(méi)有keys()函數(shù)也行：
flower={'rose':10,
'orchid':16,
'carnation':8}
for flowers in flower:
print("花名：",flowers)
3.遍歷字典的值（value）
flower={'rose':10,
'orchid':16,
'carnation':8}
for flowers in flower.values():
print("價(jià)格：",flowers)
4.字典里面放字典
實(shí)例：人物介紹
role={
'魯班':{
'技能':'土木建筑',
'職業(yè)':'工匠'
},
'鐘無(wú)艷':{
'技能':'出謀劃策',
'職業(yè)':'中國(guó)古代四大丑女之一'
},
'蔡文姬':{
'技能':'琴棋書(shū)畫',
'職業(yè)':'董祀之妻'
}
}
for a,b in role.items():
print("姓名：",a)
print("介紹：",b)
三、簡(jiǎn)單介紹下函數(shù)
len()：求元素個(gè)數(shù)
get()：搜尋字典的key
格式：返回值=字典名.get('key')
pop()：刪除元素
格式：返回值=字典名.pop('key')
到此這篇關(guān)于python基礎(chǔ)知識(shí)之字典(Dict)的文章就介紹到這了,更多相關(guān)python 字典 Dict內(nèi)容請(qǐng)搜索腳本之家以前的文章或繼續(xù)瀏覽下面的相關(guān)文章希望大家以后多多支持腳本之家！
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