The line is the most basic object in AutoCAD. You can create a variety of lines—single lines, and multiple line segments with and without arcs. In general, you draw lines by specifying coordinate points. Lines when created, inherit the current settings from the drawing database, such as layer, linetype and color.
直线是 AutoCAD 中最基本的对象。用户可以创建各种直线—单一直线、带圆弧和不带圆弧的多线段。通常，可以通过指定坐标点来绘制直线。直线被创建后，它会从图形数据库继承当前设置，像图层、线型和颜色。
To create a line, you create a new instance of one of the following objects:
若要创建直线，可以创建下列任一个对象的新实例：
NotePolyline2D objects are the legacy polyline objects that were in AutoCAD prior to Release 14, and the Polyline object represents the new optimized polyline that was introduced with AutoCAD Release 14.
注意Polyline2D 对象是从 AutoCAD 先前的 Release 14 版本遗留下来的, 而多段线对象表示 AutoCAD Release 14 开始引入的新的优化多段线。
