如何从两个点之间的文本框中获取文本

Question

i just want to get a text from textbox that is betwen two dots for example. www. abc.org . h

Answer 1

in C#

string url = "www.google.com";
string[] split_strings = url.Split('.');
Console.WriteLine(split_strings[1]); 

Get String From Textbox:

string url = textbox_url.Text;
string[] split_strings = url.Split('.');
Console.WriteLine(split_strings[1]); 

But please, use try and catch ;)

Answer 2

You'll need to be a bit more specific with your question I think. Now, if you're just looking to extract the middle part of the address, something like the following should do the job:

var parts = textbox.Text.Split(new char[] {'.'});
if (parts.Length < 3) throw new InvalidOperationException("Invalid address.");
var middlePart = parts[1];

Answer 3

string haystack= "www.google.com"; string needle = "google";

        string myWord = GetWordFromString(haystack, needle);

        private string GetWordFromString(string haystack, string needle)
        {
           if (haystack.ToLower().Contains(needle))
           {
               return needle;
           }
        }

I re-read the post with comments I can see that you probably don't know what word you are going to extract... I think the first answer is the one that you are looking fore.

There's also regular expressions for extracting the domainname out of a url if that is your specific need. Something like this:

    public static string ExtractDomainName(string Url)
    {
        return System.Text.RegularExpressions.Regex.Replace(
        Url,
        @"^([a-zA-Z]+:\/\/)?([^\/]+)\/.*?$",
        "$2"
        );
    } 

Answer 4

Is that as specific as your requirement is?

does it only have to work for www.SOMESITE.com

what about other tld extensions like, .net, .org, .co.uk, .ie etc... what about other subdomains like, www2., api., news. etc... what about domains with no subdomain like, google.com, theregister.co.uk, bit.ly

if that's a simple as your requirement is,

then

textBox.Text.Replace("www.", "").Replace(".com", "");

though I've a feeling you haven't thought through or fully explained your requirements.

If it is a more complex scenario, you might want to look at Regular expressions.

Answer 5

string text = "www. abc.org . h";
int left = Math.Max(text.IndexOf('.'), 0),
   right = Math.Min(text.LastIndexOf('.'), text.Length - 1);

string result = text.Substring(left+1, right - left-1).Trim();