程序前面加一句：axlDBControl('maxNameLength 255)

感谢各位的解答，我是在修改过allegro_long_name_size之后没有效果才问的问题。
现在原因找到了：allegro_long_name_size这个东西在setup->user Preferences和setup->design parameters中都有，按help说到design parameters中没发现（可能是眼力太差），就直接写在了env里，其实这个参数写在env中对当前的设计文件是没有效果的，所以程序还是有问题，现在解决了，再次感谢各位的热心解答，以后还要多多学习啊。

楼上正解，默认为31，最长可以通过设置allegro_long_name_size变量来实现255的最大值

我只是想说....楼主你要把资料看全阿....你图里的31^4中的4只是一个上标而已，在资料下面有1~4的说明....
我来贴一下内容...

1 Allows lower case for general text unless on a special layer where it may adhere to more restrictive rules; for example, many layers show Refdes.

2 File names adhere to operating systems restrictions except if they are stored in the database, where they assume the least common denominator. For example, a .psm file becomes a package symbol in the database so its least common denominator is the package name restriction. Spaces in the name are not supported. It is strongly suggested that you use lower case, especially for those names stored in the tool database.

3 Directory names follow operating system limitations. The layout editor supports spaces in directory names on Windows.

4 The default maximum number of characters is 31. You can set the initial length for new designs to a maximum length of 255 by using the allegro_long_name_size environment variable (choose Setup - User Preferences (enved command)). You can change the size in existing designs by choosing Setup - Design Parameters (prmed command) and specifying a new maximum for the Long Name Size parameter in the Design tab.

已经说了很清楚了，就是限制值就是31啊。。

學習了

可以把代码贴上来看下