Jquery AspNet Core 3.1-如何获取控制器实例？

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？？？如果未声明，则为方法的断开签名

此控制器对我不起作用。我已经实现了@Red建议的代码，但是我调用了这个方法，我无法获得controller的实例

public static class ControllerExtensions { public static async Task RenderViewAsync(this Controller controller, string viewName, TModel model, bool partial = false) { if (string.IsNullOrEmpty(viewName)) { viewName = controller.ControllerContext.ActionDescriptor.ActionName; }

controller.ViewData.Model = model;

        using (var writer = new StringWriter())
        {
            IViewEngine viewEngine = controller.HttpContext.RequestServices.GetService(typeof(ICompositeViewEngine)) as ICompositeViewEngine;
            ViewEngineResult viewResult = viewEngine.FindView(controller.ControllerContext, viewName, !partial);

            if (viewResult.Success == false)
            {
                return $"A view with the name {viewName} could not be found";
            }

            ViewContext viewContext = new ViewContext(
                controller.ControllerContext,
                viewResult.View,
                controller.ViewData,
                controller.TempData,
                writer,
                new HtmlHelperOptions()
            );

            await viewResult.View.RenderAsync(viewContext);

            return writer.GetStringBuilder().ToString();
        }

public static class ControllerExtensions { public static async Task RenderViewAsync(this Controller controller, string viewName, TModel model, bool partial = false) { if (string.IsNullOrEmpty(viewName)) { viewName = controller.ControllerContext.ActionDescriptor.ActionName; }

controller.ViewData.Model = model;

        using (var writer = new StringWriter())
        {
            IViewEngine viewEngine = controller.HttpContext.RequestServices.GetService(typeof(ICompositeViewEngine)) as ICompositeViewEngine;
            ViewEngineResult viewResult = viewEngine.FindView(controller.ControllerContext, viewName, !partial);

            if (viewResult.Success == false)
            {
                return $"A view with the name {viewName} could not be found";
            }

            ViewContext viewContext = new ViewContext(
                controller.ControllerContext,
                viewResult.View,
                controller.ViewData,
                controller.TempData,
                writer,
                new HtmlHelperOptions()
            );

            await viewResult.View.RenderAsync(viewContext);

            return writer.GetStringBuilder().ToString();
        }