Single Responsibility Principle (SRP)says that "THERE SHOULD NEVER BE MORE THAN ONE REASON FOR A CLASS TO CHANGE.". Although this article mentions only about class, I think the SRP also applies to methods within the class: there should never be more than one reason for a method to change.
Visual Studio provides a good way to mark off section of file in the form of "region"so they can be collapsible and the code can be organized. Many people use region in a big method to organize the code. For example:
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| public void CreeateOrder(/*some parameters*/){ #region Validate the parameters //code goes here #endregion #region create the order //insert the order data in the database #endregion #region create the order item //insert the item data in the database #endregion} |
Note that not all people use regions like this. Many people use comments instead of regions in this kind of methods.
As you can see this is a clear violation of the single responsibility principle. The method does more than one thing: it validates the order data, create a top level order and create order items. This can certainly be put into separate method.
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| private bool ValidateOrderData(/*some parameters*/){ #region Validate the parameters //code goes here #endregion}private bool InsertOrder(/*order related parameter*/){ #region create the order //insert the order data in the database #endregion}private bool InsertOrderItem(/*order item related parameter*/){ #region create the order item //insert the item data in the database #endregion}public void CreateOrder(/*Some parameter*/){ If(ValidateOrder(/*parameter list*/)) { if(InsertOrder(/*order parameter*/)) { InsertOrderItem(/*order item parameter*/); } }} |
As you can see, wherever you are using "region" in your method to demarcate the code, you can very well put that code in a separate method.