adding letters to string

Say I start of with an empty string x=''

And I input something random say 'd' I would like x='d' then If I input a second thing say 'e' I would like x to then display x='de' and so on

Thanks

[per isakson]

Input how?

Answer 1

[Walter Roberson]

x = 'd'
x(end+1) = 'e'

Answer 2

[per isakson]

Assuming "input" means that a user inputs letters interactively

str = '';
buf = {''};
while not( isempty( buf ) )
    str = cat( 2, str, buf{1} );
    buf = inputdlg( 'input one letter: ' );
end
str

and quit the loop with the [Cancel] button