Memory Cache in C#

var cache = new MemoryCache("demoCache");

var cacheItem = new CacheItem("fullName", "Jaimin Shethiya");

var cacheItemPolicy = new CacheItemPolicy
{
AbsoluteExpiration = DateTimeOffset.Now.AddSeconds(60.0)
};

var result = cache.Add(cacheItem, cacheItemPolicy);

var result = cache.Add("fullName", "Jaimin Shethiya", cacheItemPolicy);

bool Add(string key, object value, DateTimeOffset absoluteExpiration)

The first parameter is the key of the cache entry.

The second parameter is the value of the cache entry.

The third parameter is the expiry of the time we have stored the data in the cache.

Here is an example of how to add data to the memory cache.

var result = cache.Add("fullName", "Jaimin Shethiya", DateTimeOffset.Now.AddMinutes(10));

It will return a true or false. True means it added data successfully to the cache and false means it added data unsuccessfully to the cache.

Also, the set method is available for added/stored data in the memory cache.

The same approach is available for the Add method we have learned.

void Set(CacheItem item, CacheItemPolicy policy)

The first parameter cache item class initializes and stores the key and value data.

The second parameter cache item policy class initializes and sets the expiration time and other settings.

Here is an example of how to set data in the memory cache.

cache.Set(cacheItem, cacheItemPolicy);

void Set(string key, object value, CacheItemPolicy policy)

The first parameter is the key of the cache entry.

The second parameter is the value of the cache entry.

The third parameter is the cache item policy of the cache entry.

Here is an example of how to set data in the memory cache.

cache.Set("fullName", "Jaimin Shethiya", cacheItemPolicy);

void Set(string key, object value, DateTimeOffset absoluteExpiration)

The first parameter is the key of the cache entry.

The second parameter is the value of the cache entry.

The third parameter is the expiry of the time we have stored the data in the cache.

Here is an example of how to set data in the memory cache.

cache.Set("fullName", "Jaimin Shethiya", DateTimeOffset.Now.AddMinutes(10));

Contains

This is used for whether the key is already added to the cache or not.

Syntax

bool Contains(string key)

Here is an example of how to check contained data in the memory cache.

var isExists = cache.Contains("fullName");

It will return a true or false, true means exist the key to the cache and false means not exist the key in the cache.

How to retrieve the data from the cache?

object Get(string key)

It will return a value that we have stored in the cache. if not getting any result then also do not throw any error but they have returned as a null value.

Here is an example of how to get data from a memory cache.

var value = cache.Get("fullName");

Return the full name we have stored in the memory cache "Jaimin Shethiya"

CacheItem GetCacheItem(string key)

It will return a cache item class whatever we have stored in the memory cache.

Here is an example of how to get a cache item from the memory cache.

var result = cache.GetCacheItem("fullName");
Console.WriteLine("fullName {0}", result.Value);

GetCount

It will return the number of the count whatever we have stored the data in the memory cache.

Here is an example of how to get a count from the memory cache.

var result = cache.GetCount("fullName");
Console.WriteLine("total {0}", result);

Remove

It will help remove any data from the cache and return that key value if exists otherwise return a null value.

Syntax

object Remove(string key)

Here is an example of how to remove any key from the cache.

var result = cache.Remove("fullName");
Console.WriteLine("fullName {0}", result);

GetValues

It will return multiple values from the object.

Syntax

IDictionary<string, object> GetValues(IEnumerable<string> keys)

Here is an example.

cache.Add(cacheItem, cacheItemPolicy);
cache.Add(new CacheItem("firstName", "Jaimin"), cacheItemPolicy);
cache.Add(new CacheItem("lastName", "Shethiya"), cacheItemPolicy);
var result = cache.GetValues(new string[] { "firstName", "lastName", "fullName" });
foreach (var item in result)
{
Console.WriteLine($"{item.Key} : {item.Value}");
}

Add or get existing data from the cache.

CacheItem AddOrGetExisting(CacheItem item, CacheItemPolicy policy)

If already added, then it will return data in the cache item class but the value is a null return.

Here is an example

var item = cache.AddOrGetExisting(new CacheItem("middleName", "Ashwinbhai"), cacheItemPolicy);
Console.WriteLine(item.Value);

Another example is the already added key in the cache and again added. Then it will return as a cache item data with all the values.

Here is the example.

var item = cache.AddOrGetExisting(cacheItem, cacheItemPolicy);
Console.WriteLine(item.Value);

Happy coding, enjoy coding!!!