Python - Dictionary筆記

Python的字典(Dictionary)就是雜湊(Hash)，運用方式一模一樣，只是說法的不同。
一個字典Key(鍵) & Value(值)可以是任何型態，字典並沒有順序性

宣告方式
d = {}

key & value
d = {"key1":"value1", "key2":"value2", "key3":"value3"}

利用key取value
print(d["key1"]) # value1

賦予key value，已經存在key的情況下
d["key1"] = "value has been modified"
print(d["key1"]) # value has been modified

加入新的key & value，不存在key的情況下
d["key4"] = "value4"
print(d) # {'key3': 'value3', 'key2': 'value2', 'key1': 'value1', 'key4': 'value4'}

巢狀字典
d = {
"key1":"value1",
"key2":"value2",
"key3":"value3",
"key4":{"key4-1":["It","is","a","list"]}
}
print(d["key4"]["key4-1"]) # ["It","is","a","list"]
print(d["key4"]["key4-1"][1]) # is


檢查字典key

if 'key1' in d:
    pass

刪除key

del d['key1']