if you get unemployed now, and keep your membership during the period with unemployment (regardsless of the fact that you can not get unemployment benefits/dagpenge), then the full period will be included in calculating whether the 1 year membership requirement has been meet.
But You must understand that beyond the 1-year membership requirement, there is also the income-requirement. It will always take at least 1 year with income to meet the income-requirement. Only income from periods with A-kasse membership can be counted - but income from up to three years back in time can be included.
So in your case, it means that if you have worked 6 months when you lose your job, you will have to have income for further 6 months before you can get dagpenge.
So if you only have worked for example for 2 months when you lose your job, I would say there was no idea to continue A-kasse, but instead sign up again when you find a new job.
However in your case you have 6 months work/membership, that can be used in meeting the requirements, so I would keep the membership if I was you.
Anders Weber, www.a-kasser.dk