Add elements into an array when the element doesnt exist

I habe a sentence:

    string x = "This is a first string, this is a second string.";

When add every word into an array

    string[] words = x.Trim().Split(new char[] { ' ' });

What do I have to do to add only unique words into 开发者_如何学运维the array ?

Use Linq.

Also, since Split takes a params array, you don't need the new char[] part.

string[] words = x.Trim().Split(' ').Distinct().ToArray();

Use

string[] words = x.Trim().Split(new char[] { ' ' }).Distinct().ToArray();

You have to do is:

string[] words = x.Trim().Split(new char[] { ' ' }).Distinct().ToArray();

Before adding the string to array, you could traverse the array to see if word already exists.

For example:

List<string> arrayStr = new List<string>();

Before adding, you could do

if(arrayStr.Contains(abc))
MessageBox.Show("Word already exists");
else
arrayStr.Add(abc);

hope this helps