javascript testing if a value is a number AND a number greater than 0
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I have an object property that may or may not contain a number and that number may or may not be equal to 0. For the moment, I have this:

    var TheVar = parseInt(SomeObject.SomeVar, 10);
    
    if (!TheVar > 0) {
       TheVar = "-";
    }

I want `TheVar` to be either a positive number of "-". I'm just wondering if my conditional statement is going to cover every case? 

Thanks for your suggestions.