我试图拖延一个AJAX请求，使其输入单元的最后一个KEYUP发出后2-3秒。 到目前为止，我已经成功地延缓了请求，但2-3秒后，我得到一个请求派人在现场每一个KEYUP ... 如何让jQuery的取消第一个的人，只是发送最后KEYUP？ 这里的code到目前为止：

  $（'＃姓氏）。重点（函数（）{
          $（'方面：输入。）VAL（）; //清除其他搜索领域
}）。KEYUP（函数（）{
    帽（本）; //另一个函数，大写领域
    $型= $（本）.attr（ID）; //刚好路过所需的搜索类型到PHP文件
        的setTimeout（函数（）{//设置延迟每个键preSS
                ajaxSearchRequest（$类型）; //运行Ajax请求

        }，1000）;
}）;
 

这code以上，等待1秒钟，然后将取决于关键presses 4-5 AJAX请求。 我只想一个接一个，最后发送 KEYUP 我发现在StackOverflow的一些类似的解决方案，使用JavaScript，但我一直无法将其落实到我的项目，由于规划我的小知识。

[求助] 最后工作code，感谢@ Dr.Molle：

  $（'＃姓氏）。重点（函数（）{
          $（'方面：输入。）VAL（）;
}）。KEYUP（函数（）{
    帽（本）;
    $型= $（本）.attr（ID）;

    window.timer = setTimeout的（功能（）{//设置延迟每个键preSS
            ajaxSearchRequest（$类型）; //运行Ajax请求

        }，3000）;

}）KEYDOWN（函数（）{clearTimeout（window.timer）;}）;
 

这里的 ajaxSearchRequest code：

 函数ajaxSearchRequest（$型）{
                VAR ajaxRequest2; //让Ajax成为可能的变量！

                尝试{
                  //歌剧8.0+，火狐，Safari浏览器
                  ajaxRequest2 =新XMLHtt prequest（）;
                }赶上（五）{
                  // Internet Explorer浏览器
                  尝试{
                     ajaxRequest2 =新的ActiveXObject（MSXML2.XMLHTTP）;
                  }赶上（五）{
                     尝试{
                    ajaxRequest2 =新的ActiveXObject（Microsoft.XMLHTTP）;
                     }赶上（五）{
                    // 出了些问题
                    警报（浏览器的错误！）;
                    返回false;
                     }
                  }
                }

                ajaxRequest2.onreadystatechange =功能（）{
                  如果（ajaxRequest2.readyState == 4）{

                        $结果= ajaxRequest2.responseText;
                        $（'＃resultcontainer）HTML（$结果）。

                    }}


                VAR搜索关键词=的document.getElementById（$型）.value的;


                ？搜索关键词=VAR查询字符串= +搜索关键词+＆放大器;类型=+ $类型;


                如果（搜索关键词！==）{

                ajaxRequest2.open（GET，searchrequest.php+
                                 查询字符串，真实）;
                ajaxRequest2.send（空）;
                }
        }
 

解决方案

存储超时在一个变量，这样你就可以清除近期超时：

  clearTimeout（window.timer）;
window.timer = setTimeout的（功能（）{//设置延迟每个键preSS
                ajaxSearchRequest（$类型）; //运行Ajax请求

        }，3000）;
 

I am trying to delay an AJAX request so that it is sent out 2-3 seconds after the LAST keyup of an input cell. So far I have managed to delay the requests, but after 2-3 seconds I get one request sent for every keyup in the field... How can I make jQuery cancel the first ones and just send the last keyup? Here's the code so far:

$('#lastname').focus(function(){
          $('.terms :input').val(""); //clears other search fields
}).keyup(function(){
    caps(this); //another function that capitalizes the field
    $type = $(this).attr("id"); // just passing the type of desired search to the php file
        setTimeout(function(){ // setting the delay for each keypress
                ajaxSearchRequest($type); //runs the ajax request

        }, 1000);
});

This code above, waits 1 sec then sends 4-5 AJAX requests depending on keypresses. I just want one sent after the last keyup I have found some similar solutions in StackOverflow that use Javascript, but I have not been able to implement them to my project due to my small knowledge of programming.

[SOLVED] Final working code, thanks to @Dr.Molle:

$('#lastname').focus(function(){
          $('.terms :input').val("");
}).keyup(function(){
    caps(this);
    $type = $(this).attr("id");

    window.timer=setTimeout(function(){ // setting the delay for each keypress
            ajaxSearchRequest($type); //runs the ajax request

        }, 3000);

}).keydown(function(){clearTimeout(window.timer);});

Here's the ajaxSearchRequest code:

function ajaxSearchRequest($type){
                var ajaxRequest2;  // The variable that makes Ajax possible!

                try{
                  // Opera 8.0+, Firefox, Safari
                  ajaxRequest2 = new XMLHttpRequest();
                }catch (e){
                  // Internet Explorer Browsers
                  try{
                     ajaxRequest2 = new ActiveXObject("Msxml2.XMLHTTP");
                  }catch (e) {
                     try{
                    ajaxRequest2 = new ActiveXObject("Microsoft.XMLHTTP");
                     }catch (e){
                    // Something went wrong
                    alert("Browser error!");
                    return false;
                     }
                  }
                }

                ajaxRequest2.onreadystatechange = function(){
                  if(ajaxRequest2.readyState == 4){

                        $result = ajaxRequest2.responseText;
                        $('#resultcontainer').html($result);

                    }}


                var searchterm = document.getElementById($type).value;


                var queryString ="?searchterm=" + searchterm +"&type=" +$type;


                if(searchterm !== ""){

                ajaxRequest2.open("GET", "searchrequest.php" + 
                                 queryString, true);
                ajaxRequest2.send(null);
                }
        }

store the timeout in a variable, so you will be able to clear recent timeouts:

clearTimeout(window.timer);
window.timer=setTimeout(function(){ // setting the delay for each keypress
                ajaxSearchRequest($type); //runs the ajax request

        }, 3000);