Invalid assignment left-hand side, javascript

Answer 1

x += y is shorthand for x = x + y which is not what you want here.

Either use:

var addhtml = '
';
addhtml += '
e["screen_name]
';
addhtml += '
';
addhtml += '
e["description"]
';
addhtml += '
';

or:

var addhtml = '
'
    + '
e["screen_name]
'
    + '
'
    + '
e["description"]
'
    + '
';