/// <summary>
/// 引发 <see cref="RequestQuery" /> 事件
/// </summary>
public virtual string OnRequestQuery(bool resetCount = true)
{
if (!IsLoaded)
{
return("Query has been unloaded.");
}
var msg = CanQuery();
if (msg.IsNullOrEmpty())
{
if (resetCount)
{
CurrentAlternativeIndex = null;
QueryCount = 0;
}
else
{
if (AlternativeDate.Count > 0)
{
var nindex = (CurrentAlternativeIndex ?? -1) + 1;
if (nindex >= AlternativeDate.Count)
{
CurrentAlternativeIndex = null;
}
else
{
CurrentAlternativeIndex = nindex;
}
}
}
RequestQuery?.Invoke(this, new GeneralEventArgs <bool>(resetCount));
}
return(msg);
}
