ArgumentOutOfRangeException when writing C# List<string> to multiple textbox

Question

How to put list to multiple TextBoxes? I have tried to use several way to do it. All of them can put only one value from List<string> into TextBox and show an error of System.ArgumentOutOfRangeException

Below is the code I have tried this far:

List<string> txtlist = new List<string>();
 for (int ix = 1; ix < 16; ix++)
{
   string test = command.Get(appendCommand);
   txtlist.Add(test);
   txt_1.Text = txtlist.ElementAt(0);  
   txt_2.Text = txtlist.ElementAt(1); //System.ArgumentOutOfRangeException
   txt_3.Text = txtlist.ElementAt(2);
   txt_4.Text = txtlist.ElementAt(3);
   ...
   txt_4.Text = txtlist.ElementAt(15);
}

List txtlist data show as below:

[0] "test1" [1] "test2" [2] "test3" .... [15] "test16"

I want to put list one by one to the textbox, please show me some example, thank you.

Answer 1

First build txtList and after that there are items to get. No more ArgumentOutOfRangeException

List<string> txtlist = new List<string>();
for (int i = 0; i < 16; i++)
{
   string test = command.Get(appendCommand);
   txtlist.Add(test);
}

txt_1.Text = txtlist.ElementAt(0);  
txt_2.Text = txtlist.ElementAt(1); 
txt_3.Text = txtlist.ElementAt(2);
txt_4.Text = txtlist.ElementAt(3);
...
txt_4.Text = txtlist.ElementAt(15);