JavaScript validation: regex to validate numbers with comma -

How do I use JavaScript regex to validate numbers like this?

1000.00

1000

I have tried (used string match Should not be):

  test ('2342342342sdfsdfsdf'); Function test (t) {warning (/ \ d {1,3} (, \ d {3}) * (\. \ D \ d)? | \. \ D \ d / .test (t)); }   
 But still gives me the truth.   
 
 
 I am not sure what you mean by valid but it can work.  
  // console.log is used in firebug. Var isNumber = function (str) {return! IsNaN (str.toString (). Replace (/[.///, '')); } Console.log (isNumber ('1,000.00') === true); Console.log (isNumber ('10000') === true); Console.log (isNumber ('1, ooo.00') === incorrect); Console.log (isNumber ('ten') === incorrect); Console.log (isNumber ('2342342342sdfsdfsdf') === incorrect);