条码枪扫码后input会自动提交 （亲测有效）可以区分手动输入与条码枪扫码

var lastTime = null,
	nextTime = null,
	codess = '';
	
//条码枪扫码
var myInputOrder = document.getElementById('code_new');
myInputOrder.onkeydown = function (e) {
	let keycode = e.keyCode || e.which || e.charCode;
	nextTime = new Date();
	if (keycode === 13) {
		inputisbns = myInputOrder.value;
		if (lastTime && (nextTime - lastTime < 30)) {//扫码枪
			if(inputisbns){
				相关操作
			}
		} else{//手动输入
			if(inputisbns){
				相关操作
			}
		}
		codess = '';
		lastTime = null;
		e.preventDefault();
	} else {
		if (!lastTime) {
		  codess = String.fromCharCode(keycode);
		} else {
			if (nextTime - lastTime < 30) {
				codess += String.fromCharCode(keycode);
			} else {
				codess = '';
			}
		}
		lastTime = nextTime;
	}
};

https://www.jianshu.com/p/3019858e3cad