Then, start Visual Studio Code, or open a new window if you already have it opened, and open your project's folder. You can, of course, use another editor if you prefer.
Let's examine the project structure:
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The web part file and the folder structure is similar but not the same as in the no-framework project. The main difference is that there is a components folder under the src\webparts\reactTodo web part folder. We can see that, in the ReactTodoWebPart.ts file, there is an import statement, which imports the ReactTodo class from components/ReactTodo. Also, if we examine the ReactTodoWebPart class, we can see that in the render function, instead of creating the HTML directly, we are actually creating a React element using the class definition of ReactTodo and then calling ReactDom to render it to the web part's domElement:
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Next, we open ReactTodo.tsx from the components subfolder and examine that file:
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We can see that the...