[c#] convert string array to string

I would like to convert a string array to a single string.

string[] test = new string[2];
test[0] = "Hello ";
test[1] = "World!";

I would like to have something like "Hello World!"

A slightly faster option than using the already mentioned use of the Join() method is the Concat() method. It doesn't require an empty delimiter parameter as Join() does. Example:

string[] test = new string[2];
test[0] = "Hello ";
test[1] = "World!";

string result = String.Concat(test);

hence it is likely faster.

A simple string.Concat() is what you need.

string[] test = new string[2];

test[0] = "Hello ";
test[1] = "World!";

string result = string.Concat(test);

If you also need to add a seperator (space, comma etc) then, string.Join() should be used.

string[] test = new string[2];

test[0] = "Red";
test[1] = "Blue";

string result = string.Join(",", test);

If you have to perform this on a string array with hundereds of elements than string.Join() is better by performace point of view. Just give a "" (blank) argument as seperator. StringBuilder can also be used for sake of performance, but it will make code a bit longer.

In the accepted answer, String.Join isn't best practice per its usage. String.Concat should have be used since OP included a trailing space in the first item: "Hello " (instead of using a null delimiter).

However, since OP asked for the result "Hello World!", String.Join is still the appropriate method, but the trailing whitespace should be moved to the delimiter instead.

// string[] test = new string[2];

// test[0] = "Hello ";
// test[1] = "World!";

string[] test = { "Hello", "World" }; // Alternative array creation syntax 
string result = String.Join(" ", test);

    string ConvertStringArrayToString(string[] array)
    {
        //
        // Concatenate all the elements into a StringBuilder.
        //
        StringBuilder strinbuilder = new StringBuilder();
        foreach (string value in array)
        {
            strinbuilder.Append(value);
            strinbuilder.Append(' ');
        }
        return strinbuilder.ToString();
    }

Try:

String.Join("", test);

which should return a string joining the two elements together. "" indicates that you want the strings joined together without any separators.

I used this way to make my project faster:

RichTextBox rcbCatalyst = new RichTextBox()
{
    Lines = arrayString
};
string text = rcbCatalyst.Text;
rcbCatalyst.Dispose();

return text;

RichTextBox.Text will automatically convert your array to a multiline string!

Aggregate can also be used for same.

string[] test = new string[2];
test[0] = "Hello ";
test[1] = "World!";
string joinedString = test.Aggregate((prev, current) => prev + " " + current);

Like this:

string str= test[0]+test[1];

You can also use a loop:

for(int i=0; i<2; i++)
    str += test[i];