提取两个字符之间的字符串？

Question

I want to extract email id between < >

for example.

input string : "abc" <abc@gmail.com>; "pqr" <pqr@gmail.com>; "abc" <abc@gmail.com>; "pqr" <pqr@gmail.com>;

output string : abc@gmail.com;pqr@gmail.com

Answer 1

string input = @"""abc"" <abc@gmail.com>; ""pqr"" <pqr@gmail.com>;";
var output = String.Join(";", Regex.Matches(input, @"\<(.+?)\>")
                                    .Cast<Match>()
                                    .Select(m => m.Groups[1].Value));

Answer 2

Tested

string input = "\"abc\" <abc@gmail.com>; \"pqr\" <pqr@gmail.com>;";
matchedValuesConcatenated = string.Join(";", 
                                Regex.Matches(input, @"(?<=<)([^>]+)(?=>)")
                                .Cast<Match>()
                                .Select(m => m.Value));

(?<=<) is a non capturing look behind so < is part of the search but not included in the output

The capturing group is anything not > one or more times

Can also use non capturing groups @"(?:<)([^>]+)(?:>)"

The answer from LB +1 is also correct. I just did not realize it was correct until I wrote an answer myself.

Answer 3

Without regex, you can use this:

public static string GetStringBetweenCharacters(string input, char charFrom, char charTo)
    {
        int posFrom = input.IndexOf(charFrom);
        if (posFrom != -1) //if found char
        {
            int posTo = input.IndexOf(charTo, posFrom + 1);
            if (posTo != -1) //if found char
            {
                return input.Substring(posFrom + 1, posTo - posFrom - 1);
            }
        }

        return string.Empty;
    }

And then:

GetStringBetweenCharacters("\\"abc\\" <abc@gmail.com>;", '<', '>')

you will get

abc@gmail.com

Answer 4

Use the String.IndexOf(char, int) method to search for < starting at a given index in the string (eg the last index that you found a > character at, ie at the end of the previous e-mail address - or 0 when looking for the first address).

Write a loop that repeats for as long as you find another < character, and everytime you find a < character, look for the next > character. Use the String.Substring(int, int) method to extract the e-mail address whose start and end position is then known to you.

Answer 5

Could use the following regex and some linq.

        var regex = new Regex(@"\<(.*?)\>");
        var input= @"""abc"" <abc@gmail.com>;  ""pqr""  <pqr@gmail.com>";
        var matches = regex.Matches(input);
       var res = string.Join(";", matches.Cast<Match>().Select(x => x.Value.Replace("<","").Replace(">","")).ToArray());

The <> brackets get removed afterwards, you could also integrate it into Regex I guess.

Answer 6

string str = "\"abc\" <abc@gmail.com>; \"pqr\" <pqr@gmail.com>;";
        string output = string.Empty;
        while (str != string.Empty)
        {
            output += str.Substring(str.IndexOf("<") + 1, str.IndexOf(">") -1);
            str = str.Substring(str.IndexOf(">") + 2, str.Length - str.IndexOf(">") - 2).Trim();
        }