39 lines
1.4 KiB
C#
39 lines
1.4 KiB
C#
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private void btnGet_Click(object sender, EventArgs e)
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{
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//Obtain a reference to the default MemoryCache instance.
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//Note that you can create multiple MemoryCache(s) inside
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//of a single application.
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ObjectCache cache = MemoryCache.Default;
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//In this example the cache is storing the contents of a file string
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fileContents = cache["filecontents"] as string;
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//If the file contents are not currently in the cache, then
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//the contents are read from disk and placed in the cache.
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if (fileContents == null)
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{
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//A CacheItemPolicy object holds all the pieces of cache
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//dependency and cache expiration metadata related to a single
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//cache entry.
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CacheItemPolicy policy = new CacheItemPolicy();
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//Build up the information necessary to create a file dependency.
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//In this case we just need the file path of the file on disk.
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List filePaths = new List();
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filePaths.Add("c:\\data.txt");
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//In the new cache API, dependencies are called "change monitors".
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//For this example we want the cache entry to be automatically expired
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//if the contents on disk change. A HostFileChangeMonitor provides
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//this functionality.
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policy.ChangeMonitors.Add(new HostFileChangeMonitor(filePaths));
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//Fetch the file's contents
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fileContents = File.ReadAllText("c:\\data.txt");
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//And then store the file's contents in the cache
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cache.Set("filecontents", fileContents, policy);
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}
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MessageBox.Show(fileContents);
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}
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