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How to get the MyController Show url programatically?
/MyController/Show/123

public ActionResult Show(int id )
{
    var completeURL = Request.RawUrl;
    var relativePath = Request.Path;
    var uriObject = Request.Url;
}

var url = Url.Action("Show", "MyController", new {id = 123});

public ActionResult Index()
{
    return RedirectToAction("Show", "MyController", new {id = 123});
}