![]() But wait, what if some customer wants to enforce 8 character password? You have to modify your apex code for this which is not a good idea. You implement the logic, everything works fine and everybody is enjoying your manages package service. So lets say, you are using a managed package and you want to validate user password to have minimum 6 characters. Use Interface to make it completely dynamic One challenge you will still see, that you need to specify your Class Type in 2nd line, which kind of does not suit our need as we need it completely dynamic. Here is how you can do it: Type t = Type.forName('YourClassName') //Create a type object using class name YourClassName newObj = (YourClassName)t.newInstance() //create a instance using Type object and TypeCast to your class Override this.CreateInstance : string * bool * * * obj * many of you are aware that after summer 12 release, we can create Apex Class instance dynamically just by using class name? Yes, no need to specify class type to create class instance. Virtual System::Object ^ CreateInstance(System::String ^ typeName, bool ignoreCase, System::Reflection::BindingFlags bindingAttr, System::Reflection::Binder ^ binder, cli::array ^ args, System::Globalization::CultureInfo ^ culture, cli::array ^ activationAttributes) public virtual object? CreateInstance (string typeName, bool ignoreCase, bindingAttr, ? binder, object? args, ? culture, object? activationAttributes) public virtual object CreateInstance (string typeName, bool ignoreCase, bindingAttr, binder, object args, culture, object activationAttributes) public object CreateInstance (string typeName, bool ignoreCase, bindingAttr, binder, object args, culture, object activationAttributes) abstract member CreateInstance : string * bool * * * obj * * obj -> obj Locates the specified type from this assembly and creates an instance of it using the system activator, with optional case-sensitive search and having the specified culture, arguments, and binding and activation attributes. The type doesn't exist in the current Assembly instance. You haven't specified the fully qualified name of the type. If the runtime is unable to find typeName in the Assembly instance, it returns null instead of throwing an exception. ' Instantiated a Person object whose value is 'John' In my example, if Målass had a 'Foo' property, you still couldnt access it via the mbc variable because not all types that can be in the variable will have a 'Foo' property, they may have 'Bar' instead. ' Unable to instantiate a Person object with Assembly.CreateInstance(String) If a class has a no-argument constructor, then creating an object from its package-qualified class name (for example, ' ') is usually done using these methods: If arguments need to be passed to the constructor, then these alternatives may be used instead: The most common use of reflection is to instantiate a class whose. Remember, to access a class property directly in code, you need an instance of that class in an appropriately typed variable. ![]() (But there are trade-offs, so it might not always be a good idea. Therefore, using reflection might be a good idea when your programs code is a useful source of data. ' The example displays the following output: Fundamentally, reflection means using the code of your program as data. Please note that Class.newInstance() can only invoke the no-arg constructor. Person p = (Person) assem.CreateInstance("") Ĭonsole.WriteLine("Instantiated a object.", Class clazz ReflectionCreateObjects.class Constructor constructor1 clazz.getConstructor(String.class) ReflectionCreateObjects obj1 constructor1.newInstance('testVar') Instantiate a new object with Class object.If the attribute names arent known at compile-time, you have to use a more normal. using System Īssembly assem = typeof(Person).Assembly CS also has class syntax to instantiate objects, the details of which. The following example defines a Person class and calls the CreateInstance(String) method to instantiate it. TypeName requires a dependent assembly that was compiled for a version of the runtime that is later than the currently loaded version. TypeName requires a dependent assembly, but the file is not a valid assembly.
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