在回调函数中调用 onSubmit 会导致无限循环

Question

我正在比较日期start_date和end_date的 2 个变量，并允许仅在end_date大于 start_date 的情况下提交表单，否则拒绝要提交的表单，但在运行此代码时，它会进入无限循环，如果我使用 getXMLWait（） 而不是 getXML（checkDateDiff） 进行异步，则移动 API 不支持它。

此外，还有很多客户端脚本可以帮助比较日期，但移动 API 不支持这些脚本。

function onSubmit() {
    var requestType = g_form.getValue('request_type');
    if (requestType == 'mifi') {
        console.log("calling validateTravelEndDate()");
        validateTravelEndDate();
        return false;
    } else
        return true;
}
//Helper function which calls a AJAX script include called "ClientDateTimeUtils" which gives the response in a callback where i am deciding whether to submit the form or not based on the status of days result.
function validateTravelEndDate() {
    var startDate = g_form.getValue('travel_start'); //First Date/Time field
    var endDate = g_form.getValue('travel_end'); //Second Date/Time field
    var dttype = 'day'; //this can be day, hour, minute, second. By default it will return seconds.
    console.log("startDate :" + startDate + "endDate :" + endDate);
    var ajax = new GlideAjax('ClientDateTimeUtils'); // This is the script include which can be used for date validation.
    ajax.addParam('sysparm_name', 'getDateTimeDiff');
    ajax.addParam('sysparm_fdt', startDate);
    ajax.addParam('sysparm_sdt', endDate);
    ajax.addParam('sysparm_difftype', dttype);
    console.log("before " + g_form.getValue('travel_end'));
    ajax.getXML(checkDateDiff);
}
// callback function where deciding to go ahead or not with form submission.
function checkDateDiff(response) {
    var answer = response.responseXML.documentElement.getAttribute("answer");
console.log("difference in days:" + answer);
    if (answer <= 0) {
        alert("Travel End date must be after Travel Start date.");
        g_form.setValue('travel_end', '');
        g_form.showFieldMsg('travel_end', 'Please provide a future date', 'error');
       return false;
 } else {
      console.log("%%%%%%%%%%%%%%% Calling g_form.submit()");
      g_form.submit(); // This has some issue as it’s going in the infinite loop and if we just return true/false from here as it’s asynchronous call , it’s not handled by the onSubmit function
  }
}

Answer 1

onSubmit()函数

始终返回mifi请求的false。 onSubmit（） 函数在返回 true 时可以执行更安全的提交。此外，g_form函数不能在回调函数中运行，因为它是在服务器上执行的。

与其在checkDateDiff函数的末尾有一个g_form.submit()，不如让onSubmit()函数返回true。

这样的事情应该有效。我评论了我更改的每一行：

function onSubmit() {
    var requestType = g_form.getValue('request_type');
    if (requestType == 'mifi') {
        console.log("calling validateTravelEndDate()");
        // **CHANGED CODE: instead of g_form.submit(), this will return true
        if(validateTravelEndDate()){
            return true;
        }
        else{
            return false;
        }
    } else
        return true;
}
//Helper function which calls a AJAX script include called "ClientDateTimeUtils" which gives the response in a callback where i am deciding whether to submit the form or not based on the status of days result.
function validateTravelEndDate() {
    var startDate = g_form.getValue('travel_start'); //First Date/Time field
    var endDate = g_form.getValue('travel_end'); //Second Date/Time field
    var dttype = 'day'; //this can be day, hour, minute, second. By default it will return seconds.
    console.log("startDate :" + startDate + "endDate :" + endDate);
    var ajax = new GlideAjax('ClientDateTimeUtils'); // This is the script include which can be used for date validation.
    ajax.addParam('sysparm_name', 'getDateTimeDiff');
    ajax.addParam('sysparm_fdt', startDate);
    ajax.addParam('sysparm_sdt', endDate);
    ajax.addParam('sysparm_difftype', dttype);
    console.log("before " + g_form.getValue('travel_end'));
    // **CHANGED CODE: validateTravelEndDate returns the callback value
    return ajax.getXML(checkDateDiff);
}
// callback function where deciding to go ahead or not with form submission.
function checkDateDiff(response) {
    var answer = response.responseXML.documentElement.getAttribute("answer");
    console.log("difference in days:" + answer);
    if (answer <= 0) {
        alert("Travel End date must be after Travel Start date.");
        g_form.setValue('travel_end', '');
        g_form.showFieldMsg('travel_end', 'Please provide a future date', 'error');
        return false;
    }
    else {
    // **CHANGED CODE: checkDateDiff will return true
        return true;
    }
}