> For the complete documentation index, see [llms.txt](https://manual-1-3.karamba3d.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://manual-1-3.karamba3d.com/chinese_1_3_3/3-in-depth-component-reference/3.3-cross-section/3.3.10-cross-section-selector.md).

# 3.3.10: 断面选择器 (Cross Section Selector)

**“CroSecSelect（选择断面）”**运算器用于从断面列表中按照名称或索引选择断面。在**“Name|Ind（名称|索引）”**输入端口中提供所需断面的名称或索引。断面名称不区分大小写。“＃”之后的所有字符均视为备注。可使用正则表达式进行选择（以“＆”开头）。断面名称区分大小写。列表索引从零开始。

**“CroSecSelect（选择断面）”**允许用户通过**“Elems|Ids”**输入端口指定应配有特定断面的梁，而**“Assemble（模型构建）”**运算器则设置相应元素的断面。此外，还可将断面直接接入元素创建运算器中。

如果**“CroSec（断面）”**输入端口上未提供断面列表，程序则默认使用Karamba3D随机附带的断面表。

![图3.3.10.1：从标准断面列表中选取具有四种不同断面的悬臂](/files/-M9XuTzAX4YKWxPG-RUQ)


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