Js正則校驗

//只能輸入包含2爲小數以內的正浮點數
var oneCount = parseFloat(KaTeX parse error: Undefined control sequence: \d at position 34: … var ex = /^(\̲d̲+|\d+\.\d{1,2})/;
if (ex.test(oneCount)) {
} else {
$_this.val(’’)
return
}