Capitalize the first letter of a string without touching the others

问题

I'm wanting to capitalize the fist letter of a string but leave the rest

What I have: racEcar

What I want: RacEcar

回答1:

Then just capitalize the first letter with str.upper() and concatenate the rest unchanged

string[0].upper() + string[1:]

Demo:

>>> string = 'racEcar'
>>> string[0].upper() + string[1:]
'RacEcar'

回答2:

You should do like Martijn suggests, but to make your function more robust, slice up to the first letter, so that you don't error on an empty string:

>>> rc = 'racEcar'
>>> newrc = rc[:1].upper() + rc[1:]
>>> newrc
'RacEcar'

so define a function that does this:

def capfirst(s):
    return s[:1].upper() + s[1:]

and then:

>>> capfirst(rc)
'RacEcar'
>>> capfirst('')
''

回答3:

This has already been stated but I decided to show it.

Using capitalize() does what you want without extra work. For example,

def Cap1(string):
    # will not error if empty, and only does the first letter of the first word.
    return string.capitalize()

Using title() may require extra work if you have multiple words. For example,

let's assume your string is: "i want pizza"

def cap2(string):
    return string.title()

The output would be: "I Want Pizza"

Another way you can use upper() is:

def cap3(string):
    if not len(string) == 0: 
        return string[0].upper()

来源：https://stackoverflow.com/questions/31767622/capitalize-the-first-letter-of-a-string-without-touching-the-others