[ruby] Ruby: How to get the first character of a string

How can I get the first character in a string using Ruby?

Ultimately what I'm doing is taking someone's last name and just creating an initial out of it.

So if the string was "Smith" I just want "S".

In MRI 1.8.7 or greater:

'foobarbaz'.each_char.first

Another option that hasn't been mentioned yet:

> "Smith".slice(0)
#=> "S"

Because of an annoying design choice in Ruby before 1.9 — some_string[0] returns the character code of the first character — the most portable way to write this is some_string[0,1], which tells it to get a substring at index 0 that's 1 character long.

>> s = 'Smith'                                                          
=> "Smith"                                                              
>> s[0]                                                                 
=> "S"                                                        

You can also use truncate

> 'Smith'.truncate(1, omission: '')
#=> "S"

or for additional formatting:

> 'Smith'.truncate(4)
#=> "S..."

> 'Smith'.truncate(2, omission: '.')
#=> "S."

In Rails

name = 'Smith'
name.first 

"Smith"[0..0]

works in both ruby 1.8 and ruby 1.9.

If you use a recent version of Ruby (1.9.0 or later), the following should work:

'Smith'[0] # => 'S'

If you use either 1.9.0+ or 1.8.7, the following should work:

'Smith'.chars.first # => 'S'

If you use a version older than 1.8.7, this should work:

'Smith'.split(//).first # => 'S'

Note that 'Smith'[0,1] does not work on 1.8, it will not give you the first character, it will only give you the first byte.

Try this:

>> a = "Smith"
>> a[0]
=> "S"

OR

>> "Smith".chr
#=> "S"

Any of these methods will work:

name = 'Smith'
puts name.[0..0] # => S
puts name.[0] # => S
puts name.[0,1] # => S
puts name.[0].chr # => S

Try this:

def word(string, num)
    string = 'Smith'
    string[0..(num-1)]
end

For completeness sake, since Ruby 1.9 String#chr returns the first character of a string. Its still available in 2.0 and 2.1.

"Smith".chr    #=> "S"

http://ruby-doc.org/core-1.9.3/String.html#method-i-chr