修复:切线捕捉画线错误

src/Add-on/DrawLine.ts

@@ -143,55 +143,43 @@ export class DrawLine implements Command
             if (ptRes.Status === PromptStatus.OK)
             {
                 //第一个是切点 第二个也是选切点
-                if (ptRes.SnapMode === ObjectSnapMode.Tan && firstSnapModeIsTan && firstTangeCircle && pts.length === 1)
+                if (ptRes.SnapMode === ObjectSnapMode.Tan && firstSnapModeIsTan && firstTangeCircle && pts.length === 1 && ptRes.SnapEntity)
                 {
-                    if (!ptRes.SnapEntity)
+                    let secondTangeCircle = ptRes.SnapEntity as Circle;
+                    //计算最优切线
+                    let lines = CircleInternalTangentLines(firstTangeCircle as Circle, secondTangeCircle).concat(CircleOuterTangentLines(firstTangeCircle as Circle, secondTangeCircle as Circle));
+                    if (!lines?.length)
                     {
                         AppToaster.show({
-                            message: "程序错误!无法获取捕捉圆,请重试!",
+                            message: "选择的点位无法构成切线",
                             timeout: 3000,
                             intent: Intent.WARNING,
                         });
                         continue;
                     }
-                    else
-                    {
-                        let secondTangeCircle = ptRes.SnapEntity as Circle;
-                        //计算最优切线
-                        let lines = CircleInternalTangentLines(firstTangeCircle as Circle, secondTangeCircle).concat(CircleOuterTangentLines(firstTangeCircle as Circle, secondTangeCircle as Circle));
-                        if (!lines?.length)
-                        {
-                            AppToaster.show({
-                                message: "选择的点位无法构成切线",
-                                timeout: 3000,
-                                intent: Intent.WARNING,
-                            });
-                            continue;
-                        }
 
-                        let minDistance = Infinity;
-                        let distance = Infinity;
-                        let nearestObjectIndex = -1;
+                    let minDistance = Infinity;
+                    let distance = Infinity;
+                    let nearestObjectIndex = -1;
 
-                        for (let i = 0; i < lines.length; i++)
+                    for (let i = 0; i < lines.length; i++)
+                    {
+                        distance = line.StartPoint.distanceTo(lines[i].StartPoint);
+                        if (distance < minDistance)
                         {
-                            distance = line.StartPoint.distanceTo(lines[i].StartPoint);
-                            if (distance < minDistance)
-                            {
-                                minDistance = distance;
-                                nearestObjectIndex = i;
-                            }
+                            minDistance = distance;
+                            nearestObjectIndex = i;
                         }
-                        line = lines[nearestObjectIndex];
+                    }
+                    line = lines[nearestObjectIndex];
 
-                        app.LayoutTool.AppendDatabaseSpace(line);
+                    app.LayoutTool.AppendDatabaseSpace(line);
 
-                        drawLines.push(line);
-                        ptLast = line.EndPoint;
-                        pts.push(ptLast);
-                        JigUtils.Destroy();
-                        continue;
-                    }
+                    drawLines.push(line);
+                    ptLast = line.EndPoint;
+                    pts.push(ptLast);
+                    JigUtils.Destroy();
+                    continue;
                 }
                 //正常画线
                 line.EndPoint = ptRes.Point;