如何實現RazorViewEngine FindView緩存

Question

我正在繼承RazorViewEngine，我試圖重寫FindView，並且我很難以使用ViewLocationCache實現緩存。

任何人都可以舉個例子嗎？

Answer 1

我終於明白了。 這裏是我的整個實施：

public override ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName, bool useCache) 
    { 
     //Implement defualt exceptions 
     if(controllerContext == null) 
      throw new ArgumentNullException("The controllerContext parameter is null"); 
     if(string.IsNullOrEmpty(viewName)) 
      throw new ArgumentException("The viewName parameter is null or empty."); 

     //Check cache if specified 
     if(useCache && this.ViewLocationCache != null){ 
      string cachedLocation = ViewLocationCache.GetViewLocation(controllerContext.HttpContext, generateCacheKey(controllerContext, viewName)); 
      if (!string.IsNullOrEmpty(cachedLocation)) 
       return new ViewEngineResult(CreateView(controllerContext, cachedLocation, masterName), this); 
     } 

     //Create arguments for location formatting 
     string trimmedViewName = string.Empty; 
     if (viewName.EndsWith(".cshtml")) 
      trimmedViewName = viewName.Remove(viewName.Length - 7); 
     else 
      trimmedViewName = viewName; 
     object[] args = new object[] { trimmedViewName, controllerContext.RouteData.GetRequiredString("controller"), controllerContext.RouteData.GetRequiredString("module") }; 

     //Attempt to locate file 
     List<string> searchedLocations = new List<string>(); 
     foreach(string location in ViewLocationFormats){ 
      string formatedLocation = string.Format(location,args); 
      searchedLocations.Add(formatedLocation); 
      if (FileExists(controllerContext, formatedLocation)) 
      { 
       //File has been found. Add to cache and return view 
       if(this.ViewLocationCache != null) 
        ViewLocationCache.InsertViewLocation(controllerContext.HttpContext, generateCacheKey(controllerContext, viewName), formatedLocation); 

       return new ViewEngineResult(CreateView(controllerContext, formatedLocation, masterName), this); 
      } 
     } 

     //Couldnt find view, return searched locations 
     return new ViewEngineResult(searchedLocations); 
    } 
    public string generateCacheKey(ControllerContext controllerContext, string viewName) 
    { 
     return string.Format("{0}|{1}", controllerContext.RouteData.GetRequiredString("module"), viewName); 
    }