我需要填写一些下拉boxex一些参考数据。即城市名单,世界各国及地区等。我需要填写它在不同的web表单。我认为,我们应该缓存这个数据在我们的应用程序,这样,我们没有任何形式的对撞数据库。我是新来的缓存和ASP.Net。请建议我如何做到这一点。
I need to fill some dropdown boxex from some reference data. i.e City List, Country List etc. I need to fill it in various webforms. I think, we should cache this data in our application so that, we don't hit database on every form. I am new to caching and ASP.Net. Please suggest me how to do this.
我随时添加下面的类来我所有的项目,让我轻松访问缓存的对象。实现这个,下面哈桑·汗的回答将是一个很好的路要走。
I always add the following class to all my projects which give me easy access to the Cache object. Implementing this, following Hasan Khan's answer would be a good way to go.
public static class CacheHelper
{
/// <summary>
/// Insert value into the cache using
/// appropriate name/value pairs
/// </summary>
/// <typeparam name="T">Type of cached item</typeparam>
/// <param name="o">Item to be cached</param>
/// <param name="key">Name of item</param>
public static void Add<T>(T o, string key, double Timeout)
{
HttpContext.Current.Cache.Insert(
key,
o,
null,
DateTime.Now.AddMinutes(Timeout),
System.Web.Caching.Cache.NoSlidingExpiration);
}
/// <summary>
/// Remove item from cache
/// </summary>
/// <param name="key">Name of cached item</param>
public static void Clear(string key)
{
HttpContext.Current.Cache.Remove(key);
}
/// <summary>
/// Check for item in cache
/// </summary>
/// <param name="key">Name of cached item</param>
/// <returns></returns>
public static bool Exists(string key)
{
return HttpContext.Current.Cache[key] != null;
}
/// <summary>
/// Retrieve cached item
/// </summary>
/// <typeparam name="T">Type of cached item</typeparam>
/// <param name="key">Name of cached item</param>
/// <param name="value">Cached value. Default(T) if item doesn't exist.</param>
/// <returns>Cached item as type</returns>
public static bool Get<T>(string key, out T value)
{
try
{
if (!Exists(key))
{
value = default(T);
return false;
}
value = (T)HttpContext.Current.Cache[key];
}
catch
{
value = default(T);
return false;
}
return true;
}
}