Differences between defining bindings in MXML and ActionScript

Question :Differences between defining bindings in MXML and ActionScript?
Answer :: There are a few differences between defining data bindings in MXML at compile time and in
defining them at runtime in ActionScript:
* You cannot include ActionScript code in a data binding expression defined by the bindProperty()
or bindSetter() method. Instead, use the bindSetter() method to specify a method to call when the
binding occurs.
* You cannot include an E4X expression in a data binding expression defined in ActionScript.
* You cannot include functions or array elements in property chains in a data binding expression
defined by the bindProperty() or bindSetter() method. For more information on property chains, see
Working with bindable property chains.
* The MXML compiler has better warning and error detection support than runtime data bindings
defined by the bindProperty() or bindSetter() method.