1.定義

eng2sp = {}   # 定義空字典
eng2sp['one'] = 'uno'
eng2sp['two'] = 'dos'
print eng2sp
print eng2sp['two']        # 字典查詢：通過key查詢value
eng2sp[2] = 'hdi'          # 字典沒有順序
print eng2sp

2.常見操作

inventory = {'apples': 430, 'bananas': 312,'oranges': 525, 'pears': 217}
# 修改
inventory['bananas'] = 0
print inventory
 
# 刪除
del inventory['bananas']
print inventory
# 計數
print len(inventory)
# 清空
inventory.clear()
print inventory

3.別名和拷貝

inventory = {'apples': 430, 'bananas': 312,'oranges': 525, 'pears': 217}
alias = inventory
copy1 = inventory.copy()                #alias和inventory指向同一個值。而copy1則指向全新的拷貝
alias['bananas
 
'] = 33
print inventory['bananas']              #如果修改alias，inventory也發生變化。
copy1['bananas'] = 56
print inventory['bananas']              #如果修改copy1，inventory則不會發生變化。

4.get用法

letterCounts = {}
for letter in "Mississippi":
    letterCounts[letter] = letterCounts.get (letter, 0) + 1
print letterCounts          #
 
打印出每個字母出現的次數