JS正則表達式檢驗數字或者帶小數點的數字

1.
 var patrn = /^\d+(\.\d+)?$/;
 var num = 0.11; if (!patrn.exec(num)){
 alert("請您輸入數字");return;
 }
2.
 var patten = /^[+-]?(0|([1-9]\d*))(\.\d+)?$/g;
 var num = 0.11;
 if(!patten.test(num)){
    alert("請您輸入數字");return;
 }