SOURCE

var aid = "01012";
var flist = [
    {
        "attrCode": "01",
        "processId": "98b756e5b318495ebb1f1dd74157ee22",
        "fromId": "8EA42794B98E904AE050007F01005511a"
    },
    {
        "attrCode": "0101",
        "processId": "98b756e5b318495ebb1f1dd74157ee22",
        "fromId": "8EA42794B98E904AE050007F01005511b"
    },
    {
        "attrCode": "010201",
        "processId": "98b756e5b318495ebb1f1dd74157ee22",
        "fromId": "8EA42794B98E904AE050007F01005511c"
    },
    {
        "attrCode": "02",
        "processId": "ae0e661c2adb4591b341e03dcc901666",
        "fromId": "5e94db3a3de0f477c2f4eab1c90a4f10d"
    }
]
function test(aid, list) {
    var fromId;
    if (aid.length > 1 && !fromId) {
        $.each(list, function (i, item) {
            if (aid == item.attrCode) {
                fromId = item.fromId
                return false
            } else {
                test(aid.substr(0, aid.length - 1), list)
                return
            }
            return false
        })


    }

    return fromId;
}
console.log(999999999, test(aid, flist))