How to check if a variable is a number or a string?
RubyRuby Problem Overview
How to check if a variable is a number or a string in Ruby?
Ruby Solutions
Solution 1 - Ruby
There are several ways:
>> 1.class #=> Fixnum
>> "foo".class #=> String
>> 1.is_a? Numeric #=> true
>> "foo".is_a? String #=> true
Solution 2 - Ruby
class Object
def is_number?
to_f.to_s == to_s || to_i.to_s == to_s
end
end
> 15.is_number?
=> true
> 15.0.is_number?
=> true
> '15'.is_number?
=> true
> '15.0'.is_number?
=> true
> 'String'.is_number?
=> false
Solution 3 - Ruby
var.is_a? String
var.is_a? Numeric
Solution 4 - Ruby
The finishing_moves gem includes a String#numeric? method to accomplish this very task. The approach is the same as installero's answer, just packaged up.
"1.2".numeric?
#=> true
"1.2e34".numeric?
#=> true
"1.2.3".numeric?
#=> false
"a".numeric?
#=> false
Solution 5 - Ruby
Print its class, it will show you which type of variable is (e.g. String or Number).
e.g.:
puts varName.class
Solution 6 - Ruby
class Object
def numeric?
Float(self) != nil rescue false
end
end
Solution 7 - Ruby
if chr.to_i != 0
puts "It is number, yep"
end