python代码优化

Posted 2020-10-06

if / else 三目运算

age = 19
if age > 18:
    ji = "adult"
else:
    ji = "child"
ji = ‘adult‘ if age > 18 else ‘child‘   //这样写直接直观
print ji

 

真值判断

if attr == True:
    do_something()

if len(values) != 0: # 判断列表是否为空
    do_something()

可以直接这样写

if attr:
    do_something()

if values:
    do_something()

 

for  / else    break语句不执行时候就会执行 else语句

age = [3,6,8,2,7,8,4,67,3]
res = False
for i in age:
    if i > 60:
        res = True
        break

if not res:
    print "noooo"
else:
    print "yessssss"

//使用 for / else 进行判断

for i in age:
    if i > 60:
        print "yesssssss"
        break
else:
    print "nooooooooo"

获取字典元素

dic = {"name":"jk","age":23}

if dic.has_key("name"):
    print dic[‘name‘]
else:
    print "no name attr"

print dic.get("name","no name attr")