Passing array to FormBuilder in Symfony2
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I would like to create a form which has multiple input fields corresponding to the elements of an array. In ASP.Net MVC 3 I had the ModelBuilder that encoded information about the underlying model inside the input HTML tags and rebuild the model automatically on POST but I haven't managed to find something similar in Symfony2.   
Could anyone tell me whether in Symfony2 there is a way of telling the FormBuilder that the field it receives by calling the add method is actually an array?