18. Reflection

In C# is the ability to inspect and interact with types, objects, and members dynamically at runtime; it is useful for scenarios like code analysis, serialization, and creating extensible frameworks.

• When GetGetMethod().IsVirtual is used, it typically serves to determine whether a property is an overridden property in a derived class or an original property in the base class.

• BindingFlags.Instance: This value can be passed to the GetMembers, GetFields, GetProperties, and GetMethods methods of the Type class to specify that you only want to retrieve the instance members of the type.

• It’s important to note: In prop.GetType().IsClass, GetType() is a method of the System.Object class. On the other hand, in prop.PropertyType.IsPrimitive, PropertyType is a property of System.Reflection. Finally, in prop is decimal, the is keyword checks whether the value of prop is of type decimal; however, it does not confirm the data type itself.

var properties = obj.GetType().GetProperties();
 
foreach (PropertyInfo prop in properties)
 
if (prop.PropertyType.IsClass)
 
    console.Writeline(prop.Name);

• In Regression

  • PropertyInfo[] _properties;
    • When dealing with a large number of properties in a class (where a property refers to an auto-implemented getter and setter), we declare a PropertyInfo[] _properties array object that holds all the properties for a specific class.

• Recursion property.GetValue(obj, null);

  • A System.StackOverflowException will occur if I do not use property.GetValue(obj, null) because it retrieves the value from the object and terminates recursion.

• Generic Method public void Insert<T>(T item) {} When we use <T>, it indicates that the method can accept only that specific type. Example: Insert<string>("Hello world");

• IEnumerable Interface

  • Once an object has been cast to the IEnumerable interface, it can be used to iterate over its elements using a foreach loop or other methods that accept an IEnumerable object.

• Data Types

  • Dynamic Type
    • Skips type-checking at compile time.
    • Defers type-checking until runtime.
    • All syntax checks are performed, and errors are thrown at runtime.
  • Var Type
    • Type-checking occurs at compile time.

• Cascade Feature

  • Normal StringBuilder usage:

    var sb = new StringBuilder();    
    sb.Append("Hello");     
    sb.Append("World");

• Using the cascade feature:

var sb = new StringBuilder().Append("Hello").Append("World");