重复JavaScript AJAX请求，直到状态更改

Question

我使用AJAX从PHP文件制作和检索API调用，然后使用jQuery IF语句显示某些数据。

返回的数据带有几种不同的状态，例如：＆＃34; Ready＆＃34;，＆＃34;正在进行＆＃34;，＆＃34; DNS＆＃34;和＆＃34;错误＆＃34;。每个状态都有一条消息随附。

对于一个特定的状态，＆＃34;正在进行＆＃34;，我想继续循环使用JavaScript函数，直到状态变为其他状态。如果状态是＆＃34;正在进行＆＃34;，它可能需要1分钟才能更改，所以如果可能的话，我想以5秒的间隔循环使用JavaScript功能。

我在下面包含了我的jQuery。

    $(document).ready(function() {

    //Stops the submit request
    $("#myAjaxRequestForm").submit(function(e){
           e.preventDefault();
    });

    //checks for the button click event
    $("#myButton").click(function(e){
           $("#ajaxResponse").empty();
            //get the form data and then serialize that
            dataString = $("#myAjaxRequestForm").serialize();

            //get the form data using another method
            var hostName = $("input#hostName").val();
            dataString = "host=" + hostName;

            //make the AJAX request, dataType is set to json
            //meaning we are expecting JSON data in response from the server
            $.ajax({
                type: "GET",
        url: "api.php",
                data: dataString,
                dataType: "json",

                //if received a response from the server
                success: function( response ){
                var data = response.status;
                    if ((data == 'READY' && response.endpoints[0].statusMessage == 'Ready' )) {
                    $("#ajaxResponse").append("<b>Status:</b> " + response.endpoints[0].statusMessage+ "<br>");
                    $("#ajaxResponse").append("<b>Host:</b> " + response.host+ "<br>");
                    $("#ajaxResponse").append("<b>Port:</b> " + response.port+ "<br>");
                    $("#ajaxResponse").append("<h3>Endpoint [0]</h3><b>Server Name:</b> " + response.endpoints[0].serverName+ "<br>");
                    $("#ajaxResponse").append("<b>IP Address:</b> " + response.endpoints[0].ipAddress+ "<br>");
                    $("#ajaxResponse").append("<b>Grade:</b> " + response.endpoints[0].grade+ "<br>");
                    $("#ajaxResponse").append("<h3>Endpoint [1]</h3><b>Server Name:</b> " + response.endpoints[1].serverName+ "<br>");
                    $("#ajaxResponse").append("<b>IP Address:</b> " + response.endpoints[1].ipAddress+ "<br>");
                    $("#ajaxResponse").append("<b>Grade:</b> " + response.endpoints[1].grade+ "<br>");
                    $("#ajaxResponse").append("<h3>Endpoint [2]</h3><b>Server Name:</b> " + response.endpoints[2].serverName+ "<br>");
                    $("#ajaxResponse").append("<b>IP Address:</b> " + response.endpoints[2].ipAddress+ "<br>");
                    $("#ajaxResponse").append("<b>Grade:</b> " + response.endpoints[2].grade+ "<br>");
                     }
                    else if ((data == 'READY' && response.endpoints[0].statusMessage != 'Ready')) {
                        $("#ajaxResponse").append("<b>Status: </b>" +response.endpoints[0].statusMessage+ "<br>");
                        $("#ajaxResponse").append("<b>Server Name: </b>" + response.endpoints[0].serverName+ "<br>");
                        $("#ajaxResponse").append("<b>IP Address: </b>" + response.endpoints[0].ipAddress+ "<br>");
                     }
                     else if (data == "DNS") {
                         $("#ajaxResponse").html("<div><b>No cached result found.<br><br>" +response.statusMessage+ "<br>..please wait a few mins and try again.</b></div>");
                     }
                     else if (data == "IN_PROGRESS") {
                         $("#ajaxResponse").html("<div><b>No cached result found.<br><br>" +response.endpoints[0].statusMessage+ "<br>..please wait a few mins and try again.</b></div>");
                     }
                     else if (data == "ERROR") {
                         $("#ajaxResponse").html("<div><b>Error.<br><br>" +response.statusMessage+ "<br></b></div>");
                     }
                     else {
                         $("#ajaxResponse").html("<div><b>error</b></div>");
                     }
                },

            });       
    });

});

Answer 1

将AJAX请求移动到一个函数（例如doAjax（）），以便您可以根据需要调用它。单击按钮时调用doAjax（）。当返回的状态为＆＃34; In Progress＆＃34;时，使用setTimeout（）在5秒后递归调用相同的函数。

AJAX请求大约每5秒发出一次，直到状态不是＆＃34;进行中＆＃34;。 （我说＆＃34;大致＆＃34;因为AJAX请求本身需要时间，并且在请求完成后5秒延迟开始。）

更新了JavaScript：

$(document).ready(function () {

    //Stops the submit request
    $("#myAjaxRequestForm").submit(function (e) {
        e.preventDefault();
    });

    //checks for the button click event
    $("#myButton").click(function (e) {
        e.preventDefault(); // Prevent default button click action
        doAjax();
    });

});

function doAjax() {
    //$("#ajaxResponse").empty(); Move this to reduce appearance of refreshing
    //get the form data and then serialize that
    dataString = $("#myAjaxRequestForm").serialize();

    //get the form data using another method
    var hostName = $("input#hostName").val();
    dataString = "host=" + hostName;

    //make the AJAX request, dataType is set to json
    //meaning we are expecting JSON data in response from the server
    $.ajax({
        type: "GET",
        url: "api.php",
        data: dataString,
        dataType: "json",

        //if received a response from the server
        success: function (response) {
            var data = response.status;
            if ((data == 'READY' && response.endpoints[0].statusMessage == 'Ready')) {
                $("#ajaxResponse").empty();
                $("#ajaxResponse").append("<b>Status:</b> " + response.endpoints[0].statusMessage + "<br>");
                $("#ajaxResponse").append("<b>Host:</b> " + response.host + "<br>");
                $("#ajaxResponse").append("<b>Port:</b> " + response.port + "<br>");
                $("#ajaxResponse").append("<h3>Endpoint [0]</h3><b>Server Name:</b> " + response.endpoints[0].serverName + "<br>");
                $("#ajaxResponse").append("<b>IP Address:</b> " + response.endpoints[0].ipAddress + "<br>");
                $("#ajaxResponse").append("<b>Grade:</b> " + response.endpoints[0].grade + "<br>");
                $("#ajaxResponse").append("<h3>Endpoint [1]</h3><b>Server Name:</b> " + response.endpoints[1].serverName + "<br>");
                $("#ajaxResponse").append("<b>IP Address:</b> " + response.endpoints[1].ipAddress + "<br>");
                $("#ajaxResponse").append("<b>Grade:</b> " + response.endpoints[1].grade + "<br>");
                $("#ajaxResponse").append("<h3>Endpoint [2]</h3><b>Server Name:</b> " + response.endpoints[2].serverName + "<br>");
                $("#ajaxResponse").append("<b>IP Address:</b> " + response.endpoints[2].ipAddress + "<br>");
                $("#ajaxResponse").append("<b>Grade:</b> " + response.endpoints[2].grade + "<br>");
            } else if ((data == 'READY' && response.endpoints[0].statusMessage != 'Ready')) {
                $("#ajaxResponse").empty();
                $("#ajaxResponse").append("<b>Status: </b>" + response.endpoints[0].statusMessage + "<br>");
                $("#ajaxResponse").append("<b>Server Name: </b>" + response.endpoints[0].serverName + "<br>");
                $("#ajaxResponse").append("<b>IP Address: </b>" + response.endpoints[0].ipAddress + "<br>");
            } else if (data == "DNS") {
                $("#ajaxResponse").html("<div><b>No cached result found.<br><br>" + response.statusMessage + "<br>..please wait a few mins and try again.</b></div>");
            } else if (data == "IN_PROGRESS") {
                $("#ajaxResponse").html("<div><b>No cached result found.<br><br>" + response.endpoints[0].statusMessage + "<br>..please wait a few mins and try again.</b></div>");
                // Call this function again after 5 seconds
                setTimeout(function () {
                    doAjax();
                }, 5000);
            } else if (data == "ERROR") {
                $("#ajaxResponse").html("<div><b>Error.<br><br>" + response.statusMessage + "<br></b></div>");
            } else {
                $("#ajaxResponse").html("<div><b>error</b></div>");
            }
        },

    });
}