Elegant python-enhanced formatted string format function

Since python2.6, a new function Str.format () that formats the string has been added to the power. So, what's the advantage of being compared to the previous% format string? Let us uncover the veil of its shy.

Grammar

It replaces% with {} and:.

Map sample

By location

字符串的format函数可以接受不限个参数，位置可以不按顺序，可以不用或者用多次，不过2.6不能为空{}，2.7才可以。
通过关键字参数

通过对象属性

通过下标

有了这些便捷的“映射”方式，我们就有了偷懒利器。基本的Python知识告诉我们，list和tuple可以通过“打散”成普通参数给函数，而dict可以打散成关键字参数给函数（通过和*）。所以可以轻松的传个list/tuple/dict给format函数。非常灵活。

Format qualifier

It has a rich "format qualifier" (syntax is {} with:), such as:

Fill and Align
Padding is used in conjunction with alignment
^, <, > center, Align Left, right, back with width
: The fill character after the number, only one character, not specified by default is filled with a space
Like what

In [15]: ‘{:>8}‘.format(‘189‘)Out[15]: ‘     189‘In [16]: ‘{:0>8}‘.format(‘189‘)Out[16]: ‘00000189‘In [17]: ‘{:a>8}‘.format(‘189‘)Out[17]: ‘aaaaa189‘

accuracy and type F
Accuracy is often used in conjunction with Type F

其中.2表示长度为2的精度，f表示float类型。

Other Types
Mainly in the system, B, D, O, X are binary, decimal, octal, hexadecimal.

用，号还能用来做金额的千位分隔符。

in [+]: ' {:,} '. Format (1234567890) out[47]: ' 1,234,567,890 '

Elegant python-enhanced formatted string format function