SHJX_GM/SHJX.Service.WorkFlowEdit/Common/CustomMoveResizeTool.cs

using Aga.Diagrams;
using Aga.Diagrams.Tools;
using System.Linq;

namespace FlowWorkEditDemo
{
    class CustomMoveResizeTool : MoveResizeTool
    {
        private FlowchartModel _model;

        public CustomMoveResizeTool(DiagramView view, FlowchartModel model) : base(view)
        {
            _model = model;
        }

        public override bool CanDrop()
        {
            foreach (var item in DragItems)
            {
                var column = (int)(item.Bounds.X / View.GridCellSize.Width);
                var row = (int)(item.Bounds.Y / View.GridCellSize.Height);
                if (_model.Nodes.Where(p => !IsDragged(p) && p.Row == row && p.Column == column).Count() != 0)
                    return false;
            }
            return true;
        }

        private bool IsDragged(FlowNode node)
        {
            return DragItems.Where(p => p.ModelElement == node).Count() > 0;
        }
    }
}