Help me see what's going on with the alert infinite pop-up window in the code.

</script>
<script>
    // 
    function isChinaName(name) {
        var pattern = /^[\u4E00-\u9FA5]{1,6}$/;
        return pattern.test(name);
    }
    // 
    function isCardNo(card) {
        var pattern = /(^\d{15}$)|(^\d{18}$)|(^\d{17}(\d|X|x)$)/;
        return pattern.test(card);
    }
    // 
    function isPhoneNo(phone) {
        var pattern = /^1[34578]\d{9}$/;
        return pattern.test(phone);
    }


    /**/
    function userName(inputid) {
        $(inputid).blur(function() {
            if ($.trim($(inputid).val()).length != "") {
                return true;
            } else {
                alert("")
                return false;
            }
        });
        $(inputid).focus(function() {
            return false;
        });

    };
    userName("-sharpusername");

    /**/
    function userID(inputid) {
        // window.alert = function(){ return false; }
        $(inputid).blur(function() {
            if ($.trim($(inputid).val()).length == "") {
                alert("");
                return false;
            } else {
                if (isCardNo($.trim($(inputid).val())) == false) {
                    alert("");
                    return false;
                }
            }
        });
        $(inputid).focus(function() {
            return false;
        });
    };
    userID("-sharpID-number");

    /**/
    function userTel(inputid) {
        $(inputid).blur(function() {
            if ($.trim($(inputid).val()).length == 0) {
                alert("");
                return false;
            } else {
                if (isPhoneNo($.trim($(inputid).val())) == false) {
                    alert("");
                    return false;
                }
            }
            $(inputid).focus(function() {
                return true;
            });
        });
    };
    userTel("-sharptelephone");
</script>
</html>```
Oct.28,2021

.. The way you ask this question is too rough.
you directly search ide for where there is alert and see how it is triggered. Besides,

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1c3708f-3387d.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1c3708f-3387d.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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