Modified the negative condition checks, removing the ! negation, replacing with an explicit false check.

This is a matter of coding style / personal preference, the C# compiler doesn't care, it's the same IL.
I've come to feel that the explicit `false` check feels more semantic, (and in my old age, I've often missed the leading "!" - oops!)

Author: leekelleher

src/Our.Umbraco.DocTypeGridEditor/Extensions/ViewEnginesCollectionExtensions.cs

@@ -9,7 +9,7 @@ public static bool ViewExists(
             ControllerContext controllerContext,
             string viewName, bool isPartial = false)
         {
-            var result = !isPartial
+            var result = isPartial == false
                 ? viewEngines.FindView(controllerContext, viewName, null)
                 : viewEngines.FindPartialView(controllerContext, viewName);
 

src/Our.Umbraco.DocTypeGridEditor/PackageActions/AddObjectToJsonArray.cs

@@ -45,7 +45,7 @@ public bool Execute(string packageName, XmlNode xmlData)
                 var trg = HttpContext.Current.Server.MapPath(GetTargetFileName(xmlData));
                 var propKey = GetKeyProperty(xmlData);
 
-                if (!File.Exists(src) || !File.Exists(trg))
+                if (File.Exists(src) == false || File.Exists(trg) == false)
                     return false;
 
                 var srcJson = File.ReadAllText(src);

src/Our.Umbraco.DocTypeGridEditor/Web/Controllers/DocTypeGridEditorApiController.cs

@@ -50,7 +50,7 @@ public object GetContentTypeIcon([ModelBinder] string contentTypeAlias)
             var contentType = Services.ContentTypeService.GetContentType(contentTypeAlias);
             return new
             {
-                icon = contentType != null ? contentType.Icon : ""
+                icon = contentType != null ? contentType.Icon : string.Empty
             };
         }
 

src/Our.Umbraco.DocTypeGridEditor/Web/Controllers/DocTypeGridEditorSurfaceController.cs

@@ -49,14 +49,14 @@ protected PartialViewResult CurrentPartialView(object model = null)
 
         protected override PartialViewResult PartialView(string viewName, object model)
         {
-            if (IsPreview && !string.IsNullOrWhiteSpace(PreviewViewPath))
+            if (IsPreview && string.IsNullOrWhiteSpace(PreviewViewPath) == false)
             {
                 var previewViewPath = GetFullViewPath(viewName, PreviewViewPath);
                 if (ViewEngines.Engines.ViewExists(ControllerContext, previewViewPath, true))
                     return base.PartialView(previewViewPath, model);
             }
 
-            if (!string.IsNullOrWhiteSpace(ViewPath))
+            if (string.IsNullOrWhiteSpace(ViewPath) == false)
             {
                 var viewPath = GetFullViewPath(viewName, ViewPath);
                 if (ViewEngines.Engines.ViewExists(ControllerContext, viewPath, true))

src/Our.Umbraco.DocTypeGridEditor/Web/Helpers/SurfaceControllerHelper.cs

@@ -66,7 +66,7 @@ public static bool SurfaceControllerExists(string controllerName, string actionN
 
         public static bool SurfaceControllerExists(string name, string actionName = "Index", bool cacheResult = true)
         {
-            if (!cacheResult)
+            if (cacheResult == false)
                 return SurfaceControllerExists(name, actionName);
 
             return (bool)ApplicationContext.Current.ApplicationCache.RuntimeCache.GetCacheItem(