ruby 正则表达式 - 如何匹配直到字符的所有内容 -

Question

given a string as follow:

randomstring1-randomstring2-3df83eeff2

How can I use a ruby regex or some other ruby/rails friendly method to find everything up until the first dash -

In the example above that would be: randomstring1

Thanks

Answer 1

You can use this pattern: ^[^\-]*

Answer 2

mystring = "randomstring1-randomstring2-3df83eeff2"
firstPart = mystring[0, mystring.index("-")]

Otherwise, I think the best regex is @polishchuk's.

It matches from the beginning of the string, matches as many as possible of anything that is not a dash - .

Answer 3

Using irb you can do this too:

>> a= "randomstring1-randomstring2-3df83eeff2"
=> "randomstring1-randomstring2-3df83eeff2"
>> a.split('-').first
=> "randomstring1"
>> 

Answer 4

For this situation, the index solution given by agent-j is probably better. If you did want to use regular expressions, the following non-greedy (specified by the ? ) regex would grab it:

(^.*?)-

You can see it in Rubular .