Python Sting 练习实践（二）

字典增删改查

Student_Info = {
'1220610001':'Alex',
'1220610002':'Bob',
'1220610003':'Cindy',
'1220610004':'David'}

print("info:",Student_Info)
print("pop('1220610004'):",Student_Info.pop('1220610004'))#del
print(Student_Info)
print("find 1220610001 :",Student_Info["1220610001"])#search1
print("1220610004 is in info?-->",Student_Info.get('1220610004'))#search2
print("1220610003 is in info?-->",Student_Info.get('1220610003'))#search2
print("1220610004 is in info?-->",'1220610004' in Student_Info)#search3
print("1220610003 is in info?-->",'1220610003' in Student_Info)#search3

Student_Info['1220610005']='Eric'
print(Student_Info)#add
Student_Info['1220610005']='Ellen'
print(Student_Info)#change

多级字典嵌套

Student_Info = {
'1220610001':{
'Alex':{
'English':[90, 91, 93]}},
'1220610002':{
'Bob':{
'English':[94, 95, 96]}},
'1220610003':{
'Cindy':{
'English':[97, 98, <
4000
span class="hljs-number">99]}}
}

Student_Info['1220610003']['Cindy']['English'][0]=60
print(Student_Info)
print(Student_Info.values())
print(Student_Info.keys())

Student_Info.setdefault("1220610003",{'Cindy':{'English':[10,20,30]}})#If exist, not changed
print(Student_Info)
Student_Info.setdefault("1220610004",{'David':{'English':[10,20,30]}})#If not exist, added
print(Student_Info)

字典交叉合并

Student_Info = {
'1220610001':{
'Alex':{
'English':[90, 91, 93]}},
'1220610002':{
'Bob':{
'English':[94, 95, 96]}},
'1220610003':{
'Cindy':{
'English':[97, 98, 99]}}
}

New_Student = {
'1220610001':{
'Angela':{
'English':[90, 91, 93]}},
'1220610004':{
'Daniel':{
'English':[94, 95, 96]}},
}
print(Student_Info)
Student_Info.update(New_Student)
print(Student_Info)

Change to list (items)

Student_Info = {
'1220610001':{
'Alex':{
'English':[90, 91, 93]}},
'1220610002':{
'Bob':{
'English':[94, 95, 96]}},
'1220610003':{
'Cindy':{
'English':[97, 98, 99]}}
}

info = {"Name":'Alex',"Age":25}
print(Student_Info.items())
print(info.items())

字典的循环

Student_Info = {
'1220610001':{
'Alex':{
'English':[90, 91, 93]}},
'1220610002':{
'Bob':{
'English':[94, 95, 96]}},
'1220610003':{
'Cindy':{
'English':[97, 98, 99]}}
}

for i in Student_Info:
print(i,Student_Info[i])#more efficient

print()
for k,v in Student_Info.items():
print(k,v)