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    <p>Your example is ServiceLocator. There is always a ServiceLocator somewhere. I would say the key is to understanding why you would use it directly and why ideally you might not have to.</p> <p>The key concept is the dependency inversion principal. Dependency injection and inversion of control frameworks are tools that facilitate application of the principal. Ideally you want your objects constructor parameters to be interface definitions which will be resolved at object creation time.</p> <p>If you are using modern tools, such as asp.net MVC then you have access to what is called the composition root which is the entry point of the application. In MVC it's controller. Since you have access to the composition root you don't need to use ServiceLocator because injection is driven from the top for you by your IOC framework which you would have registered and setup. Basically your controller has constructors parameters like ISomeService which is registered with IOC and injected automatically when the controller instance is created. If the ISomeService had some dependencies they would also be in the constructor as ISomeUtility, and so forth as your objects get deeper and deeper. This is ideal and you would never have need to use the ServiceLocator to resolve an object.</p> <p>If you were in a situation using technology that doesn't grant you access to the root or if you were wanting to start using an IOC framework in an application that didn't have one and you were adding it for the first time then you may find you can't get to the composition root. It could be a limitation of the framework or the quality of the code. In these cases you have to use the ServiceLocator or directly create the object yourself. In these cases using the ServiceLocator is OK and is better than creating that object yourself.</p>
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    1. PODependency injection or service location?
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    1. COThat example is from the book itself, not from me.
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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