Insert a new piece of code contain angularJS directive at runtime

You have to use $compile.

For example here, I insert new html code that contain angularjs directive (var fieldValue) in a new cell of a table.

var newCell = tblBodyObj.rows[i].insertCell(position);

$(newCell).append($compile(fieldValue)($scope));

$compile(fieldValue)($scope) return an object and you can append it to the dom.