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c# - Creating an object from from an ID (or name)

I have an abstract class that a lot of child classes inherit:

  public abstract class CrawlerBase
    {
        public abstract void Process(string url);
    }

I'm working on this loop:

foreach (var item in result)
                {
                    object crawler = null;

                    switch (item.Type)
                    {
                        case "Trials":
                            var t = new Trials(); 
                            ct.Process(item.URL); //repetitive code.  
                            break;

                        case "Coverage":
                            var c = new Coverage();
                            c.Process(item.URL); //repetitive code.
                            break;
                        default:
                            break;
                    }

                   // crawler.Process(item.URL);
                }

Now the item.type string will depend on what child class needs to be instantiated. Since all my child classes inherit my base class, it would be very repetitive to call .Process() in every case statement. I want to cast the object "crawler" to the child class being instantiated, and call the crawler.Process() at the end of the switch statement, as shown in the comments. How can I do this?

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by (71.8m points)

Does this not work?

foreach (var item in result)
{
    CrawlerBase crawler = null;

    switch (item.Type)
    {
        case "Trials":
            crawler = new Trials(); 
            break;
        case "Coverage":
            crawler = new Coverage();
            break;
        default:
            break;
    }

    if(crawler != null)
        crawler.Process(item.URL);
}

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