Set Default value if textbox blank javascript function

Hi, Below is my text box in `MVC` application's view. I want that when its loaded it has default value "0"and if someone kept textbox blank it 'ill take autometically default value.
@Html.TextBoxFor(model => item.myfeild, new { placeholder = "Required", @class = "myclass", require = "true", maxlength = "1", id = @item.myid })