TestComplete中C#Script实际上是基于JScript的

The C#Script language is based on the JScript scripting language, not on the C# programming language. You can find a complete description of the C#Script language in the 'Writing C# Scripts' help topic.

In brief, this language is just a modification of the JScript language that uses the '[""]' syntax when accessing members of an object instead of the dot ('.'). This syntax is the only way to implement late binding in the C# programming language that is required by the Connected Applications feature of TestComplete. Please see the 'Connected Applications' help topic for information.

So, if you are not going to use the Connected Applications feature of TestComplete, I recommend that you use the JScript language for your tests. Actually, you will be able to use the Connected Applications feature even if you use JScript for your tests. However, in this case you will have to modify all scripts that are moved to your Connected Application.