Like operator in SQL alternative in C#

Question

I'm trying to check if any string entered after a certain message I do have a working version in SQL that I want to use almost the same one in C#

Usage in SQL:

        ELSE IF @Msg LIKE '/Message %'

Usage in C#:

        else if (Msg == "/Message ")

I want the tool to check if any string entered right after /Message.

Thanks in advance :)

Possible duplicate of [C# Version Of SQL LIKE](https://stackoverflow.com/questions/5417070/c-sharp-version-of-sql-like) — Lance U. Matthews, Jun 17 '17 at 00:02
I don't want to search for a string in a string. I want to read any possible string entered — Crepitus, Jun 17 '17 at 00:08
Are you already familiar with `string.StartsWith()`, `string.Contains()` and `string.EndsWith()`? — Rufus L, Jun 17 '17 at 00:13
I'm not understanding how the two questions differ. You want to test if `Msg` contains `"/Message "` followed by arbitrary text, and optionally retrieve and act on that arbitrary text? The linked question, as well as [the many other duplicates or near-duplicates](https://www.google.com/search?q=site%3Astackoverflow.com+c%23+like+operator), provide the building blocks for how to do that. It might be better to look at this through the lens of regular expressions, not SQL, as that is what the solution will likely involve (if not the basic `string` methods @RufusL notes). — Lance U. Matthews, Jun 17 '17 at 00:17
Which specific LIKE features do you need? See https://learn.microsoft.com/en-us/sql/t-sql/language-elements/like-transact-sql . I assume you need % but do you need _ support? [] support? [^] support? etc etc — mjwills, Jun 17 '17 at 01:53

score 3 · Answer 1 · answered Jun 17 '17 at 00:17

3

You can use the following string functions:

var Msg = "A message to check";

For LIKE 'SomeText%':

if (Msg.StartsWith("SomeText"))

For LIKE '%SomeText':

if (Msg.EndsWith("SomeText"))

For LIKE '%SomeText%':

if (Msg.Contains("SomeText"))

answered Jun 17 '17 at 00:17

Rufus L

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bic · Accepted Answer · 2017-06-17T13:19:39.107

1

Here is how the TSQL LIKE keyword works.

using System;

namespace SqlLike
{
    class Program
    {
        static void Main(string[] args)
        {
            var findMe = "ABCHelloXYZ";

            // LIKE '......%'
            if (findMe.StartsWith("ABC"))
            {
                Console.WriteLine("Yay");
            }

            // LIKE '%......'
            if (findMe.EndsWith("XYZ"))
            {
                Console.WriteLine("Woohoo");
            }

            // LIKE '%......%'
            if (findMe.Contains("Hello"))
            {
                Console.WriteLine("JackPot!!");
            }

            Console.ReadLine();
        }
    }
}

edited Jun 17 '17 at 13:19

answered Jun 17 '17 at 00:17

bic

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1

Your commented out lines are backwards. `findMe.StartsWith("....")` is the same thing as `LIKE '....%'` and `findMe.EndsWith("....")` is the same thing as `LIKE '%....'` – Scott Chamberlain Jun 17 '17 at 00:20
`"#Hello%";` Shouldn't that be `"%Hello%";`? – mjwills Jun 17 '17 at 01:51
1

@mjwills I shouldn't have used % as an example. I've updated to better illustrate what I meant. – bic Jun 17 '17 at 13:21
What if "aaa%bbb%ccc%ddd"? – VikciaR Jan 09 '20 at 06:09

DaniDev · Answer 3 · 2017-06-17T00:21:34.877

0

Your requirements are a little vague, but this should get you there (with a little adjustment as needed).

String Msg = "/Message somethingelse";
        if (Msg.Contains("/Message ") && (Msg.Length > 9) )
        {
            String str = Msg.Substring(9);
            Console.Write("str: " + str);
        }

As @Scott suggested you can also use:

if (Msg.StartsWith("/Message ") && (Msg.Length > 9))
        {
            String str = Msg.Substring(9);
            Console.Write("str: " + str);
        }

edited Jun 17 '17 at 00:21

answered Jun 17 '17 at 00:13

DaniDev

2,471
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That will also match strings that have text *before* `"/Message"` – Rufus L Jun 17 '17 at 00:14
Yes as I said the requirements are a little vague but hopefully enough to get Crepitus going – DaniDev Jun 17 '17 at 00:15
The requirement is to make code that acts like `@Msg LIKE '/Message %'`, your example acts like `@Msg LIKE '%/Message %'`. You need a `StartsWith` instead of a `Contains` – Scott Chamberlain Jun 17 '17 at 00:16
also the sql submitted indicates that the string will always start with "/Message" – DaniDev Jun 17 '17 at 00:17
thanks @Scott Chamberlain I will add your suggestion to the answer – DaniDev Jun 17 '17 at 00:19
Well, we don't see what the value of `Msg` is, but he wants to test if it starts with `/Message` – Rufus L Jun 17 '17 at 00:19

Like operator in SQL alternative in C#

3 Answers3