javascript - MVC : Get JSON data from a controller using AJAX failed

Question

我正在尝试使用 AJAX 从 Controller 查询数据，我的 Controller 是:

[HttpGet]
public ActionResult GetTestStatus(string userName)
{
    var db = new SREvalEntities();
    var allTests = db.Tests
        .Where(x => string.Equals(x.Owner, userName))
        .Select(x => new { CreateDate = x.CreateDate, EndDate = x.EndDate, Status = x.Status })
        .OrderByDescending(x => x.CreateDate)
        .ToList();

    return Json(allTests, JsonRequestBehavior.AllowGet);
}

我的外部文件中的 javascript 代码是:

function Filter() {
    var userAlias = document.getElementById("UserAliasInput");
    var txt = "<tr><th>StartDate</th><th>EndDate</th><th>Status</th><th>Detail</th></tr>";
    $.ajax({
        url: '/TestStatus/GetTestStatus',
        type: "GET",
        dataType: "JSON",
        data: { userName: userAlias },
        success: function (results) {
            $.each(results, function (i, result) {
                txt += "<tr><td>" + result.CreateDate + "</td>";
                txt += "<td>" + result.EndDate + "</td>";
                txt += "<td>" + result.Status + "</td>";
                txt += "<td><a href=\"\">Goto</a></td></tr>";
            });
        }
    });
    $("#ShowDetail").html(txt);
}

当我尝试调试这个函数时，代码永远不会执行到

$("#ShowDetail").html(txt);

我的页面永远不会改变。我怎样才能让它发挥作用？谢谢。

Answer 1

当您使用$.ajax()时，它是异步的。因此，在从 API 返回值之前调用 $("#ShowDetail").html(txt)。

您应该在每个 block 之后设置html()

function Filter() {
    var userAlias = document.getElementById("UserAliasInput");
    var txt = "<tr><th>StartDate</th><th>EndDate</th><th>Status</th><th>Detail</th></tr>";
    $.ajax({
        url: '/TestStatus/GetTestStatus',
        type: "GET",
        dataType: "JSON",
        data: { userName: userAlias.value }, //Use the value property here
        success: function (results) {
            $.each(results, function (i, result) {
                txt += "<tr><td>" + result.CreateDate + "</td>";
                txt += "<td>" + result.EndDate + "</td>";
                txt += "<td>" + result.Status + "</td>";
                txt += "<td><a href=\"\">Goto</a></td></tr>";
            });

            $("#ShowDetail").html(txt); //Move code to set text here
        }
    });    
}