List.RemoveAll – How to create an appropriate Predicate

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The RemoveAll() methods accept a Predicate<T> delegate (until here nothing new). A predicate points to a method that simply returns true or false. Of course, the RemoveAll will remove from the collection all the T instances that return True with the predicate applied.

C# 3.0 lets the developer use several methods to pass a predicate to the RemoveAll method (and not only this one…). You can use:

Lambda expressions

vehicles.RemoveAll(vehicle => vehicle.EnquiryID == 123);

Anonymous methods

vehicles.RemoveAll(delegate(Vehicle v) {
  return v.EnquiryID == 123;
});

Normal methods

vehicles.RemoveAll(VehicleCustomPredicate);
private static bool
VehicleCustomPredicate (Vehicle v) {
    return v.EnquiryID == 123; 
}

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