How to concatenate variables in cmd shell

I am writing a cmd script. Part of what I have to do requires me to concatenate the values of two variables. I've created开发者_高级运维 a variable called %mydate%, and I would like to concatenate that with a space and the value of the system variable %time%.

I've tried set mydate2 = %mydate% %time%, but it is null.

Any ideas?

TIA!

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This works for me:

set mydate2=%date% %time%

Note: %date% and %time% are just examples - they are created by the interpreter and thus always exist.