I have the following URL:
https://comanage.example.edu/sp https://wiki.cs.example.org/sp https://intranet.math.example.edu/sp https://myapp.example.com/sp
For these URLs, I need to define a function to detect whether they are URLs and replace the https:// and sp paths from them. Basically, I just need the hostname. For example, as shown below:
https://comanage.example.edu/sp ->comanage.example.edu https://wiki.cs.example.org/sp ->wiki.cs.example.org https://intranet.math.example.edu/sp ->intranet.math.example.edu https://myapp.example.com/sp ->myapp.example.com
For non-URLs, this function should detect and not replace them. As follows:
nonurl.example.com -> ***no replacement***
Can anyone provide me with a solution to the above problem? I don't have much knowledge about using regular expressions.
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Mode
^https?:\/\/should be easy to use here. We can use it to replace any string starting withhttp://andhttps://with the empty stringIn a pattern, the
at the beginning^symbol represents the beginning of a string. This means that ifhttp://appears in the middle of the string, it willnotmatch since it must be?Marks the previous character as optional. In the pattern,sis optional in order to findhttpandhttps\/is required because slashes must be escapedconst urls = [ 'https://comanage.example.edu/sp', 'https://wiki.cs.example.org/sp', 'https://intranet.math.example.edu/sp', 'https://myapp.example.com/sp', 'nonurl.example.com', ]; const pattern = /^https?:\/\//i; urls.forEach(u => { console.log(u, '-->', u.replace(pattern, '')); });