public object Execute(string commandText, object parameter = null)
{
if (string.IsNullOrWhiteSpace(commandText))
{
throw new ArgumentNullException(nameof(commandText));
}
//创建命令执行器上下文对象
var context = this.CreateExecutorContext(commandText, parameter);
if (context == null)
{
throw new InvalidOperationException("The context of this command executor is null.");
}
//创建事件参数对象
var executingArgs = new CommandExecutorExecutingEventArgs(context);
//激发“Executing”事件
this.OnExecuting(executingArgs);
if (executingArgs.Cancel)
{
return(executingArgs.Result);
}
object result = null;
try
{
//调用执行请求
result = this.OnExecute(context);
}
catch (Exception ex)
{
//激发“Error”事件
if (!this.OnFailed(context, ex))
{
throw;
}
}
//创建事件参数对象
var executedArgs = new CommandExecutorExecutedEventArgs(context, result);
//激发“Executed”事件
this.OnExecuted(executedArgs);
//返回最终的执行结果
return(executedArgs.Result);
}
protected virtual void OnExecuted(CommandExecutorExecutedEventArgs args)
{
this.Executed?.Invoke(this, args);
}
