欢迎来到MicroStation Python世界！使用MicroStation时的常见任务之一是处理围栏内的元素。本文将通过一个Python脚本演示如何管理MicroStation围栅内的元素。

让我们深入探讨在MicroStation中处理围栅内的元素，迭代它们，并对每个元素执行操作。请参阅Python管理器文章以创建和加载Python项目。将您的项目命名为FenceElements.py并将其保存到任意文件夹下。在编辑器中打开该项目以编写Python脚本。

导入模块

该脚本首先导入几个模块，这些模块提供了与MicroStation交互以及操作围栅的函数和类。

from MSPyBentley import *
from MSPyBentleyGeom import *
from MSPyECObjects import *
from MSPyDgnPlatform import *
from MSPyDgnView import *
from MSPyMstnPlatform import *

处理围栅内的元素

ProcessFenceElements()函数旨在管理和处理围栅内的元素。让我们一步步分解处理过程：

初始化：脚本首先初始化必要的几个实例：FenceManager.GetManager()、SelectionSetManager.GetManager()和WString()
检查围栅是否处于激活状态：在处理之前，脚本使用fenceMgr.IsFenceActive()检查是否存在激活的围栅。如果没有，它将打印一条消息并退出该函数
初始化围栅参数：接下来，脚本使用fenceMgr.InitFromActiveFence()将当前围栅的信息填充到提供的围栅参数中
构建元素列表：该脚本使用fenceMgr.BuildAgenda()构建符合围栅参数的元素列表
迭代围栅内的元素：脚本迭代符合围栅条件的每个元素。eeh=eAgenda.GetEntry(i)方法检索每个选定元素的可编辑元素句柄(EditElementHandle)
处理每个元素：为元素添加自定义处理逻辑，其中放置了注释#Do Something

def ProcessFenceElements():
    global ACTIVEMODEL

    # Initialize
    fenceMgr = FenceManager.GetManager()
    selSetManager = SelectionSetManager.GetManager()
    elmTypeString = WString()

    # Check of Fence is active
    if False == fenceMgr.IsFenceActive():
        print("No active fence...")
        return

    # InitFromActiveFence: Populate the supplied FenceParams with information 
    #                      for the active fence. 
    fenceParams = FenceParams(ACTIVEMODEL)
    bOverlapMode = fenceMgr.IsOverlapMode()    
    bClipMode = fenceMgr.IsClipMode()
    allowClipFlag = FenceClipMode.eOriginal
    fenceMgr.InitFromActiveFence (fenceParams, bOverlapMode, bClipMode, allowClipFlag)

    # ElementAgenda: A bvector of EditElementHandle entries to be used for 
    #                operating on groups of elements such as SelectionSet 
    #                and Fences. 
    eAgenda = ElementAgenda()
    modelRefList = DgnFile.GetModelRefList (DgnFile.GetMasterFile())
    # BuildAgenda: Collect elements that satisfy the supplied FenceParams/criteria.
    fenceMgr.BuildAgenda(fenceParams, eAgenda, modelRefList, False, False, False)

    # Clear current selection set
    selSetManager.EmptyAll()

    # Process Fence elements
    for i in range(eAgenda.GetCount()):
        # Do Something
        eeh = eAgenda.GetEntry(i)
        eeh.GetHandler().GetTypeName (elmTypeString, 100)

将以上代码集成在一起：main函数

main函数初始化当前模型并调用ProcessFenceElements()函数来处理围栏元素。

下面是完整的脚本：

from MSPyBentley import *
from MSPyBentleyGeom import *
from MSPyECObjects import *
from MSPyDgnPlatform import *
from MSPyDgnView import *
from MSPyMstnPlatform import *


# Get Level Name of Level ID passed as argument
def GetLevelName(lvlId):
    global ACTIVEMODEL    
    levelCache = ACTIVEMODEL.GetDgnFile().GetLevelCache()

    it = iter(levelCache)

    for level in it:
        levelId = level.GetLevelId()
        if lvlId == levelId:
            return level.GetName()


# Process Fence Elements
def ProcessFenceElements():
    global ACTIVEMODEL

    # Initialize
    fenceMgr = FenceManager.GetManager()
    selSetManager = SelectionSetManager.GetManager()
    elmTypeString = WString()

    # Check of Fence is active
    if False == fenceMgr.IsFenceActive():
        print("No active fence...")
        return

    # InitFromActiveFence: Populate the supplied FenceParams with information 
    #                      for the active fence. 
    fenceParams = FenceParams(ACTIVEMODEL)
    bOverlapMode = fenceMgr.IsOverlapMode()    
    bClipMode = fenceMgr.IsClipMode()
    allowClipFlag = FenceClipMode.eOriginal
    fenceMgr.InitFromActiveFence (fenceParams, bOverlapMode, bClipMode, allowClipFlag)

    # ElementAgenda: A bvector of EditElementHandle entries to be used for 
    #                operating on groups of elements such as SelectionSet 
    #                and Fences. 
    eAgenda = ElementAgenda()
    modelRefList = DgnFile.GetModelRefList (DgnFile.GetMasterFile())
    # BuildAgenda: Collect elements that satisfy the supplied FenceParams/criteria.
    fenceMgr.BuildAgenda(fenceParams, eAgenda, modelRefList, False, False, False)

    # Clear current selection set
    selSetManager.EmptyAll()

    # Process Fence elements
    for i in range(eAgenda.GetCount()):
        eeh = eAgenda.GetEntry(i)
        eeh.GetHandler().GetTypeName (elmTypeString, 100)

        msElement = MSElement()
        msElement = eeh.GetElement()        

        levelId = msElement.ehdr.level
        levelName = GetLevelName(levelId)

        selSetManager.AddElement(eeh.GetElementRef(),ACTIVEMODEL.GetDgnModel())  

        print("***")
        print(f"Element Description: {elmTypeString}")
        print(f"Element Type: {eeh.GetElementType()}, Element ID: {eeh.GetElementId()}")
        print(f"Level Name: {levelName}, Level ID: {levelId}")


# Main function
def main():
    global ACTIVEMODEL
    ACTIVEMODEL = ISessionMgr.ActiveDgnModelRef

    ProcessFenceElements()


# Main
if __name__ == "__main__":
    print("********** Fence Elements **********")
    main()

运行/执行项目

在当前模型中放置一个围栅框住一些元素，选择所需的围栅类型、模式并运行/执行Python脚本。
与围栅条件匹配的元素将被高亮显示，其信息（描述、类型、Id、层名、层Id）将显示在MicroStation文本窗口中。

此脚本提供了一个使用Python在MicroStation中处理围栅内元素的基本框架。您可以自由定制脚本以满足您的特定需求，并将其集成到您的工作流程中。

祝您编程愉快！

【注】：文中用“围栅内的元素”是为了方便描述，严格来说应该是“符合围栅条件的元素”，因为围栅模式的不同，被选中的元素有可能位于围栅外面的。

20. MicroStation Python：围栅管理器

将以上代码集成在一起：main函数