Question

VB 二次开发autocad2008中，请问如何利用VB控制获得捕捉？例如：我用VB写程序捕捉某弧度的圆心的坐标

Answer 1

ActiveDocument.SetVariable Name, Value
===========================
不懂看帮助呀，下面是帮助里的：

Sub Example_SetVariable()
' This example sets various system variables, each of
' a different data type.

Dim sysVarName As String
Dim sysVarData As Variant
Dim DataType As Integer

' Set FILEDIA system variable (data type Integer) to 1. NOTE that
' you need to declare a variable as the data type of system variable,
' assign data to that variable and then make it variant type
Dim intData As Integer
sysVarName = "FILEDIA"
intData = 1
sysVarData = intData ' Integer data
ThisDrawing.SetVariable sysVarName, sysVarData

' Check the variable using GetVariable
sysVarData = ThisDrawing.GetVariable(sysVarName)
MsgBox sysVarName & " = " & sysVarData, , "SetVariable Example"

' Set DCTCUST system variable (data type String) to "My Custom Dictionary"
Dim strData As String
sysVarName = "DCTCUST"
strData = "My Custom Dictionary"
sysVarData = strData ' String data
ThisDrawing.SetVariable sysVarName, sysVarData

' Check the variable using GetVariable
sysVarData = ThisDrawing.GetVariable(sysVarName)
MsgBox sysVarName & " = " & sysVarData, , "SetVariable Example"

' Set CHAMFERA system variable (data type Double) to 1.5
Dim dataDouble As Double
sysVarName = "CHAMFERA"
dataDouble = 1.5
sysVarData = dataDouble ' Double data
ThisDrawing.SetVariable sysVarName, sysVarData
' Check the variable using GetVariable
sysVarData = ThisDrawing.GetVariable(sysVarName)
MsgBox sysVarName & " = " & sysVarData, , "SetVariable Example"

' Set INSBASE system variable (data type array) to (1.0,1.0,0)
Dim arrayData3D(0 To 2) As Double
sysVarName = "INSBASE"
arrayData3D(0) = 1#: arrayData3D(1) = 1#: arrayData3D(2) = 0
sysVarData = arrayData3D ' 3D array data
ThisDrawing.SetVariable sysVarName, sysVarData
' Check the variable using GetVariable
sysVarData = ThisDrawing.GetVariable(sysVarName)
MsgBox sysVarName & " = " & sysVarData(0) & ", " & sysVarData(1) & ", " & sysVarData(2), , "SetVariable Example"

End Sub
==========================================
再查一下系统变量 "osmode" ,查一下什么值代表什么意思。
0

无

1

END（端点）

2

MID（中点）

4

CEN（圆心）

8

NOD（节点）

16

QUA（象限点）

32

INT（交点）

64

INS（插入点）

128

PER（垂足）

256

TAN（切点）

512

NEA（最近点）

1024

清除所有对象捕捉

2048

APP（外观交点）

4096

EXT（延伸）

8192

PAR（平行）

Answer 2

(setvar "osmode" 4)