/// <summary>
/// 在连接串映射完成后，执行映射后的动作。执行完后，恢复原有的映射
/// </summary>
/// <param name="srcConnectionName"></param>
/// <param name="destConnectionName"></param>
/// <param name="action"></param>
public static void DoMappingAction(string srcConnectionName, string destConnectionName, Action action)
{
if (action != null)
{
using (DbConnectionMappingContext context = CreateMapping(srcConnectionName, destConnectionName))
{
action();
}
}
}
private static string GetMappedConnectionContectRecursively(string srcConnectionName, HashSet <DbConnectionMappingContext> elapsedContext)
{
DbConnectionMappingContext context = null;
string result = srcConnectionName;
if (DbConnectionMappingContextCache.Instance.TryGetValue(srcConnectionName, out context))
{
if (elapsedContext.Contains(context) == false)
{
elapsedContext.Add(context);
result = GetMappedConnectionContectRecursively(context.destinationConnectionName, elapsedContext);
}
}
return(result);
}
/// <summary>
/// 释放对应关系
/// </summary>
public void Dispose()
{
DbConnectionMappingContext context = null;
if (DbConnectionMappingContextCache.Instance.TryGetValue(this.sourceConnectionName, out context))
{
if (context.originalContext != null)
{
DbConnectionMappingContextCache.Instance[this.sourceConnectionName] = context.originalContext;
}
else
{
DbConnectionMappingContextCache.Instance.Remove(this.sourceConnectionName);
}
}
GC.SuppressFinalize(this);
}
/// <summary>
/// 创建连接名称的对应关系
/// </summary>
/// <param name="srcConnectionName"></param>
/// <param name="destConnectionName"></param>
/// <returns></returns>
public static DbConnectionMappingContext CreateMapping(string srcConnectionName, string destConnectionName)
{
ExceptionHelper.CheckStringIsNullOrEmpty(srcConnectionName, "srcConnectionName");
ExceptionHelper.CheckStringIsNullOrEmpty(destConnectionName, "destConnectionName");
DbConnectionMappingContext localOriginalContext = null;
DbConnectionMappingContextCache.Instance.TryGetValue(srcConnectionName, out localOriginalContext);
DbConnectionMappingContext context = new DbConnectionMappingContext();
context.sourceConnectionName = srcConnectionName;
context.destinationConnectionName = destConnectionName;
context.originalContext = localOriginalContext;
DbConnectionMappingContextCache.Instance[context.sourceConnectionName] = context;
return(context);
}
/// <summary>
/// 获取一个DbContext对象
/// </summary>
/// <param name="name">连接名称</param>
/// <param name="autoClose">是否自动关闭</param>
/// <returns>DbContext对象</returns>
public static DbContext GetContext(string name, bool autoClose)
{
//得到映射后连接名称
name = DbConnectionMappingContext.GetMappedConnectionName(name);
DbProviderFactory factory = DbConnectionManager.GetDbProviderFactory(name);
DbConnectionStringBuilder csb = factory.CreateConnectionStringBuilder();
csb.ConnectionString = DbConnectionManager.GetConnectionString(name);
bool enlist = true;
if (csb.ContainsKey("enlist"))
{
enlist = (bool)csb["enlist"];
}
DbContext result = null;
if (enlist)
{
result = new AutoEnlistDbContext(name, autoClose);
}
else
{
result = new NotEnlistDbContext(name, autoClose);
}
result.InitDbContext(name, autoClose);
result._autoClose = autoClose;
result._commandTimeout = DbConnectionManager.GetCommandTimeout(name);
return(result);
}
