问题是您的CustomAction方法名称 CustomAction1与您提到的 DLLEntry值不匹配（ DllEntry ='CustomAction'）。您缺少 1：）

The problem is that your CustomAction method name "CustomAction1" does not match with the "DLLEntry" value which you have mentioned (DllEntry='CustomAction'). You are missing "1" :)

<CustomAction Id='CustomAction' BinaryKey='CustomAction.CA' DllEntry='CustomAction' />