在InitializeComponent（）方法中（在.designer.cs文件中）， add：

In InitializeComponent() method (in .designer.cs file), add:

txtCL_VL_LA.Enter += SetLAO;
txtCL_FN_LA.Enter += SetLAO;
txtCL_LN_LA.Enter += SetLAO;
txtCL_VL_LA.Leave += SetENG;
txtCL_FN_LA.Leave += SetENG;
txtCL_LN_LA.Leave += SetENG;

您可能必须小心将这些行放在代码文件中的位置。观察该文件的结构并确定每行的放置位置。

You may have to be careful as to where you put these lines in the code file. Observe the structure of this file and decide where to put each line.