public static void ModifyingBlockProperties()
{
DxfDocument doc = new DxfDocument();
doc.DrawingVariables.InsUnits = DrawingUnits.Centimeters;
Line existingLine = new Line(new Vector2(-10, 10), new Vector2(10, -10));
doc.AddEntity(existingLine);
AttributeDefinition attDef4 = new AttributeDefinition("MyAttribute4");
attDef4.Value = "MyValue4";
attDef4.Alignment = TextAlignment.TopCenter;
Block block = new Block("MyBlock", null, new List<AttributeDefinition>{attDef4});
block.Record.Units = DrawingUnits.Millimeters;
// this is incorrect we cannot add an entity that belongs to a document when the block does not belong to anyone.
//block.Entities.Add(existingLine);
doc.Blocks.Add(block);
// when the block and the entity that is being added belong to the same document, the entity will be removed from its current layout and added to the block
// you cannot add an entity that belongs to a different document or block. Clone it instead.
block.Entities.Add(existingLine);
// now we can modify the block properties even if it has been already added to the document
Line line = new Line(new Vector2(-10, -10), new Vector2(10, 10));
// when new entities that do not belong to anyone are added to an existing block, they will also be added to the document
block.Entities.Add(line);
DxfDocument doc2 = new DxfDocument();
Circle circle = new Circle(Vector2.Zero, 5);
doc2.AddEntity(circle);
// this is incorrect the circle already belongs to another document
//block.Entities.Add(circle);
// we need to clone it first
Circle circle2 = (Circle) circle.Clone();
circle2.Radius = 2.5;
block.Entities.Add(circle2);
//you could also remove circle2 from doc2 and add it to the block
doc2.RemoveEntity(circle);
block.Entities.Add(circle);
AttributeDefinition attDef = new AttributeDefinition("MyAttribute1");
attDef.Value = "MyValue1";
block.AttributeDefinitions.Add(attDef);
// the same that is applicable to entities is also true to attribute definitions
AttributeDefinition attDef2 = new AttributeDefinition("MyAttribute2");
attDef2.Value = "MyValue2";
attDef2.Alignment = TextAlignment.BaselineRight;
block.AttributeDefinitions.Add(attDef2);
Insert ins = new Insert(block);
doc.AddEntity(ins);
// if the insert has been added to a document, any new attribute definitions added to the block will not be reflected in the insert
// this mimics the behavior in AutoCad
AttributeDefinition attDef3 = new AttributeDefinition("MyAttribute3");
attDef3.Value = "MyValue3";
attDef3.Alignment = TextAlignment.TopCenter;
block.AttributeDefinitions.Add(attDef3);
ins.Rotation = 30;
// to update the insert attributes call the method Sync, this method will also call the method TransformAttributes
ins.Sync();
// the ins2 will have all three attributes
Insert ins2 = new Insert(block, new Vector2(20,0));
doc.AddEntity(ins2);
doc.Save("Test.dxf");
block.Name = "MyBlockRenamed";
doc.Save("BlockRename.dxf");
doc = Test("BlockRename.dxf");
}
