Question

I have the following string with a SQL command:

string sql = "select [x] from table where field = [y] order by [w], [z]";

I would like to get the keys inside the [brackets] (x, y, w, z, etc…), how could I do this with C#? Is there any way to do it with regex (not necessary)?

I try to do something with while statement but it does not work.

Thank you

Answer 1

Using Regex:

@"\[(.)]"

This will capture the letter inside the [] when using the Matches method of Regex.

Since you may have words inside the brackets, the regex is somewhat more complicated.

I will assume that these will never include an escaped ] – so the following should work:

@"\[([^\]]+)]"

Usage:

var matches = Regex.Matches("select [x] from table where field = [yy] order by [w], [z]", @"\[([^\]]+)]");

foreach(Match match in matches)
{
  foreach(Group group in match.Groups)
  {
     Console.WriteLine(group.Value);
  }
}

Note that there is a default group in match.Groups, so you will get duplicates.