System.Web.Optimization.HashCache

A helper bundle transform which prevents caching of bundle contents when optimizations are disabled - when debug is enabled or BundleTable.EnableOptimizations is false.

Get it on Nuget!

Install-Package System.Web.Optimization.HashCache

Elevator Speech

This transform prevents browsers from loading old cached versions of your code when you are running in debug mode, by adding a hash of the file content to the end of the file path:

<link href="/css/styles.css?~v=Iz7DDyL6DCDnT_L414h7aec4VUNOlN9dDYVRGoD2ZB01" rel="stylesheet"/>
<script src="/js/app.js?~v=QWNK55__txkMIVFvtdF3fy5lDLK7GLkwLzP8nzCV6nw1"></script>

Usage

You can apply HashCache to all bundles in a BundlesCollection

Execute the ApplyHashCache() extension method on the BundlesCollection Instance after all bundles have been added to the collection.

BundleTable.Bundles.ApplyHashCache();

Or you can apply HashCache to a single Bundle

Create an instance of the HashCacheTransform and add it to the bundle instance you want to apply HashCache to.

var myBundle = new ScriptBundle("~/bundle_virtual_path").Include("~/scripts/jsfile.js");
myBundle.Transforms.Add(new HashCacheTransform());

Options

• AddHashToPath: Add cache-busting content hash to the unbundled file paths output by Scripts.Render() and Styles.Render() calls.
• HttpCacheability: Disable caching bundle output in the HttpContext.Cache
• UseServerCache: Set the Cache-Control HTTP header to tell browser not to cache bundle contents.
• HashPathParameterName: Set the parameter name used in the query string when AddHashToPath is enabled. The default parameter name is "~v".

Applying Options

The above options can either be passed into the ApplyHacheCache() extension method call or set on individual instances of the HashCachTransform class.

bundles.ApplyHashCache(true, false, HttpCacheability.NoCache);)

var hashCacheTransform = new HashCacheTransform
{
    AddHashToPath = true,
    HttpCacheability = HttpCacheability.NoCache,
    UseServerCache = false
};