python格式化

1.百分号
格式如下：

%[(name)] [flags] [.precision] typecode

(name):可选，获取指定key的值
flags:可选，:width，占有宽度
.precision：可选，小数点后保留位数
typecode:必选
1)s，传入对象的__str__方法的返回值
2)c，整数
3)o，整数转八进制
4)d，整数转十进制
5)e，整数，浮点数转科学计数法
6)f，整数，浮点数转浮点数
7)F，整数，浮点数转浮点数
8)g，自动调整将整数，浮点数转浮点型或科学计数法
9)G，自动调整将整数，浮点数转浮点型或科学计数法
10)%，%%表示一个百分号

2.使用示例

result1 = "i am %s" % ‘shijingjing07‘
result2 = "i am %s, score: %d" % (‘shijingjing07‘,100)
result3 = "i am %(name)s, score: %(age)d" % ({‘name‘:‘shijingjing07‘,‘age‘:100})
result4 = "%.2f" % 99.333
result5 = "%.2f%%" % 99.333
print(result1)
print(result2)
print(result3)
print(result4)
print(result5)

运行结果：

3.format方式

result1 = ‘I am {},age {},{}‘.format(‘shijingjing‘,2,‘hello‘)
result2 = ‘I am {},age {},{}‘.format(*[‘shijingjing‘,2,‘hello‘])
result3 = ‘I am {0},age {1},{0}‘.format(‘shijingjing‘,2)
result4 = ‘I am {0},age {1},{0}‘.format(*[‘shijingjing‘,2])
result5 = ‘I am {name},age {age},{name}‘.format(**{‘name‘:‘shijingjing‘,‘age‘:18})
result6 = ‘I am {name},age {age},{name}‘.format(name=‘shijingjing‘,age=18)
result7 = ‘I am {0[0]},age {0[1]},{0[2]}‘.format([1,2,3],[4,5,6])
result8 = ‘I am {:s},age{:d}‘.format(‘shijingjing‘,2)
result8 = ‘I am {name:s},age{age:d}‘.format(name=‘shijingjing‘,age=2)
result9 = ‘numbers: {:b},{:o},{:d},{:x},{:X},{:%}‘.format(15,15,15,15,15,15.87623)
result10 = ‘numbers: {0:b},{0:o},{0:d},{0:x},{0:X},{0:%}‘.format(15)
result11 = ‘numbers: {num:b},{num:o},{num:d},{num:x},{num:X},{num:%}‘.format(num=15)
print(result1)
print(result2)
print(result3)
print(result4)
print(result5)
print(result6)
print(result7)
print(result8)
print(result9)
print(result10)
print(result11)

运行结果：