这是在code我有。我试图插入一个图像显示，Ajax是加载，但我不能得到这个权利;我尝试了很多可能的方法，但它只是不工作。在做什么有什么建议？

  ajaxRequest.onreadystatechange =功能（）{
    如果（ajaxRequest.readyState == 4）{
        变种ajaxDisplay =的document.getElementById（'main_result'）;
        ajaxDisplay.innerHTML = ajaxRequest.responseText;
    }
}
$（＃main_result）空（）的HTML。（'＆LT; IMG SRC =loading.gif/＆GT;'）;

。VAR类=的document.getElementById（'类'）值;
。VAR品牌=的document.getElementById（品牌）的价值;
VAR项目=的document.getElementById（'项目'）值。
VAR查询字符串=＆放大器;类=+分类+＆放大器;品牌=+品牌+＆放大器;项目=+项目;
ajaxRequest.open（GET，？main_search_special.php节=特殊+查询字符串，真实）;
ajaxRequest.send（空）;
 

解决方案

只是将图像添加到您的显示区域，你发送请求之前。请求完成后的结果将覆盖它。

  ...
变种ajaxDisplay =的document.getElementById（main_result）;
ajaxDisplay.innerHTML =＆其中; IMG SRC =loading.gif'/＆gt;中
ajaxRequest.send（空）;
 

This is the code I have. I'm trying to insert a image to show that ajax is loading but I just can't get this right; I tried a lot of possible ways but it just isn't working. Any suggestions on what to do?

ajaxRequest.onreadystatechange = function(){
    if(ajaxRequest.readyState == 4){
        var ajaxDisplay = document.getElementById('main_result');
        ajaxDisplay.innerHTML = ajaxRequest.responseText;
    }
}
$("#main_result").empty().html('<img src="loading.gif" />');

var category = document.getElementById('category').value;
var brand = document.getElementById('brand').value;
var item = document.getElementById('item').value;
var queryString = "&category=" + category + "&brand="+ brand +"&item="+ item;
ajaxRequest.open("GET", "main_search_special.php?section=special" + queryString, true);
ajaxRequest.send(null);

Just add the image to your display area before you send the request. The results will overwrite it when the request completes.

...
var ajaxDisplay = document.getElementById("main_result");
ajaxDisplay.innerHTML = "<img src='loading.gif' />"
ajaxRequest.send(null);