} // func GetStringArray
private async Task OpenCursorAsync(LuaTable table)
{
// not optional
var selectExpression = table.GetOptionalValue("name", (string)null) ?? throw new ArgumentNullException("name");
// parse selector
var selectorExpression = PpsDataFilterExpression.Parse(table.GetMemberValue("filter"));
// parse optional columns
var columns = PpsDataColumnExpression.Parse(table.GetMemberValue("columns")).ToArray();
// parse optional order
var orderExpressions = PpsDataOrderExpression.Parse(table.GetMemberValue("order")).ToArray();
// try to get a list
int cursorId;
lock (cursors)
cursorId = ++lastCursorId;
var cursor = new OpenCursor(cursorId, await provider.GetListAsync(selectExpression, columns, selectorExpression, orderExpressions));
lock (cursors)
cursors.Add(cursorId, cursor);
// return the cursor id
await PushPacketAsync(new LuaTable()
{
["id"] = cursorId
});
} // proc OpenCursorAsync
} // ctor
private StringBuilder ToString(StringBuilder sb)
{
sb.Append("v=");
sb.Append(ViewId);
if (Filter != null && Filter != PpsDataFilterExpression.True)
{
sb.Append("&f=").Append(Uri.EscapeDataString(Filter.ToString()));
}
if (Columns != null && Columns.Length > 0)
{
sb.Append("&r=").Append(PpsDataColumnExpression.ToString(Columns));
}
if (Order != null && Order.Length > 0)
{
sb.Append("&o=").Append(Uri.EscapeDataString(PpsDataOrderExpression.ToString(Order)));
}
if (Start != -1)
{
sb.Append("&s=").Append(Start);
}
if (Count != -1)
{
sb.Append("&c=").Append(Count);
}
if (!String.IsNullOrEmpty(AttributeSelector))
{
sb.Append("&a=").Append(AttributeSelector);
}
return(sb);
} // func ToString
/// <summary>Parse string representation from ToString.</summary>
/// <param name="data"></param>
/// <param name="list"></param>
/// <returns></returns>
public static bool TryParse(string data, out PpsDataQuery list)
{
var arguments = HttpUtility.ParseQueryString(data, Encoding.UTF8);
var viewId = arguments["v"];
if (String.IsNullOrEmpty(viewId))
{
list = null;
return(false);
}
list = new PpsDataQuery(viewId);
var f = arguments["f"];
if (!String.IsNullOrEmpty(f))
{
list.Filter = PpsDataFilterExpression.Parse(f);
}
var l = arguments["l"];
if (!String.IsNullOrEmpty(l))
{
list.Columns = PpsDataColumnExpression.Parse(l).ToArray();
}
var o = arguments["o"];
if (!String.IsNullOrEmpty(o))
{
list.Order = PpsDataOrderExpression.Parse(o).ToArray();
}
var s = arguments["s"];
if (!String.IsNullOrEmpty(s))
{
list.Start = Int32.Parse(s);
}
var c = arguments["c"];
if (!String.IsNullOrEmpty(c))
{
list.Count = Int32.Parse(c);
}
var a = arguments["a"];
if (!String.IsNullOrEmpty(a))
{
list.AttributeSelector = a;
}
return(true);
} // func TryParse
} // func CreateSelectorAsync
/// <summary>Create a selector from a select information.</summary>
/// <param name="select"></param>
/// <param name="columns"></param>
/// <param name="filter"></param>
/// <param name="order"></param>
/// <param name="throwException"></param>
/// <returns></returns>
public async Task <PpsDataSelector> CreateSelectorAsync(string select, PpsDataColumnExpression[] columns, PpsDataFilterExpression filter = null, PpsDataOrderExpression[] order = null, bool throwException = true)
{
if (String.IsNullOrEmpty(select))
{
throw new ArgumentNullException(nameof(select));
}
// create selector
var selectorInfo = new PpsViewJoinExpression(this, select, throwException);
if (!selectorInfo.IsValid && !throwException)
{
return(null);
}
// create selector
var selector = await selectorInfo.CreateSelectorAsync();
if (selector == null)
{
return(null);
}
// column restrictions
if (!PpsDataColumnExpression.IsEmpty(columns))
{
selector = selector.ApplyColumns(columns);
}
// apply filter rules
if (!PpsDataFilterExpression.IsEmpty(filter))
{
selector = selector.ApplyFilter(filter, selectorInfo.LookupFilter);
}
// apply order
if (!PpsDataOrderExpression.IsEmpty(order))
{
selector = selector.ApplyOrder(order, selectorInfo.LookupOrder);
}
return(selector);
} // func CreateSelector
