How to parse string easily?

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Replacing words in a string with values from Dictionary in c#[^]
Replacing set of words with another[^]

Maybe not the best, but this is how I would do it:

Set up a Dictionary<string,string> for all of your words. The key is "double", the value is "hello" etc.

parse the value of the textbox in it's entirety each time like so:

Dictionary<string,string> cypher = new Dictionary<string,string>
{
  {"double","hello"},
  ///etc
};

string Decode(string code){
    return code
            .split(' ')  //Split the phrase into words
            .Select(c=> 
                cypher.ContainsKey(c)  //Check the work is in the dictionary
                   ?cypher[c]          //Return the decoded word
                   :c);                //return the code word (or whatever)
}

No idea why you want this. There are much better cyphers out there that use full words and even sentences. Granted they are more complex to write codes for, though

Hope that helps ^_^

Andy

I want to give you one completely different advice though. It looks like you are looking for the easy way of doing something. This is not what decent software engineer do, when it comes to some topic really important for their work. Such people focus on different priorities: learn the subject in depth, to get the best possible competency, to get to the root of things, completely ignoring such factor as the ease of learning. If some way is harder but better, they choose the hard way. More exactly, they make their work easy enough by using their inventiveness and deep understanding of things. If your attitudes are different from that, my advice would be: leave the profession before you got major frustration.

—SA