/// <summary>
/// 如果当前命令执行上下文中的命令名称在 <paramref name="commandNames"/> 中存在则执行 <paramref name="func"/>。
/// </summary>
/// <typeparam name="T">返回值类型。</typeparam>
/// <param name="context">命令上下文。</param>
/// <param name="func">执行的动作。</param>
/// <param name="def">如果不属于 <paramref name="commandNames"/> 返回的默认值。</param>
/// <param name="commandNames">命令名称。</param>
/// <returns>返回值。</returns>
public static T Is <T>(this CommandExecuteContext context, Func <T> func, T def, params string[] commandNames)
{
if (func == null || !context.IsIn(commandNames))
{
return(def);
}
return(func());
}
/// <summary>
/// 如果当前命令执行上下文中的命令名称在 <paramref name="commandNames"/> 中存在则执行 <paramref name="action"/>。
/// </summary>
/// <param name="context">命令上下文。</param>
/// <param name="action">执行的动作。</param>
/// <param name="commandNames">命令名称。</param>
public static void Is(this CommandExecuteContext context, Action action, params string[] commandNames)
{
if (action == null || !context.IsIn(commandNames))
{
return;
}
action();
}
/// <summary> /// 执行命令。 /// </summary> /// <param name="context">命令执行上下文。</param> public abstract void Execute(CommandExecuteContext context);
/// <summary>
/// 执行命令出错时执行。
/// </summary>
/// <param name="context">命令上下文。</param>
/// <param name="exception">异常信息。</param>
/// <returns>是否抛出异常，如果需要抛出异常则返回true，否则返回false。</returns>
protected internal virtual bool Fail(CommandExecuteContext context, Exception exception)
{
context.WriteLine("执行语句 {0} 时发生了错误，详细信息：{1}", string.Join(" ", context.Args), exception);
return(false);
}
/// <summary>
/// 命令执行完成之后执行。
/// </summary>
/// <param name="context">命令上下文。</param>
public virtual void Executed(CommandExecuteContext context)
{
}
/// <summary>
/// 准备执行命令之前时执行。
/// </summary>
/// <param name="context">命令执行上下文。</param>
protected internal virtual void Executing(CommandExecuteContext context)
{
}
private static bool IsIn(this CommandExecuteContext context, IEnumerable <string> commandNames)
{
return(commandNames.Any(i => string.Equals(i, context.CommandName, StringComparison.OrdinalIgnoreCase)));
}
