Q:

How to combine two texts?

I have a Single line text box and Multiline text box, and want to include a word into the Single line text box with the words in Multiline text box per line 
Like this :
Single line text: "Hello"(I have to use variables)<br>
Multiline words:
<br>
1998<br>
1999<br>
2000

Expected results:

  Hello1998
  Hello1999
  Hello2000
  Pls Help me

I use the below code, but it is not working just with the Single line text box  and I have to manipulate by both text boxes:
string left = string.Format(add.Text , Environment.NewLine);
        string right = string.Format(textBox1.Text, Environment.NewLine);
        string[] leftSplit = left.Split(new[] { Environment.NewLine }, StringSplitOptions.None);
        string[] rightSplit = right.Split(new[] { Environment.NewLine }, StringSplitOptions.None);

        string output = "";
        if (leftSplit.Length == rightSplit.Length)
        {
            for (int i = 0; i < leftSplit.Length; i++)
            {
                output += leftSplit[i] + ":" + rightSplit[i] + Environment.NewLine;
            }
        }
        result.Text = output;

Could you please advise me on the right approach?

A:

If you have single line only one word, then no need split it into an array.
Lets consider it as a string left = "Hello";
and textbox1 contains multiline words i.e.
string right = string.Format(textBox1.Text, Environment.NewLine); // right variable contains 1998 \n 1999 \n 2000

Then you can try below approach
var concatString = right.Split(new[] { Environment.NewLine }, StringSplitOptions.None).Select(x => left + x);
string result = string.Join(Environment.NewLine , concatString);

.Net Fiddle
Output :
Hello1998
Hello1999
Hello2000

