Ajax XmlHttpRequest

Question

I have js code as well as *.txt file with some text that I want to load to the page. 我有js代码以及带有要加载到页面的一些文本的* .txt文件。

JS Code: JS代码：

 (function () {
 var link = document.getElementsByTagName("a")[0];
 link.onclick = function () {
      var xhr = new XmlHttpRequest();
      xhr.onreadystatechange = function () {
         if ((xhr.readyState == 4) && (xhr.status == 200 || xhr.status == 304)) {
                xhr.responseText;
                var body = document.getElementsByTagName("body")[0];
                var p = document.createElement("p");
                var pText = document.createTextNode(xhr.responseText);
                p.appendChild(pText);
                body.appendChild(p);
            }
        };
        xhr.open("Get", "ajax.txt", true);
        hxr.send(null);
        return false;
    };
})();

HTML Code: HTML代码：

<body>
<h1>AjaxTest</h1>
<a href="ajax.txt">Load the text from file</a>
<script src="main.js">
</script>

Everything should work. 一切都应该工作。 However ReSharper underlines XmlHttpRequest(); 但是ReSharper强调XmlHttpRequest（）; and says Use of an implicitly declared global variable" and for this xhr.responseText; it says - Expression statement is not assignment of call. What is the problem? 并针对此xhr.responseText说“ 使用隐式声明的全局变量” ；它说-Expression 语句不是调用的赋值。这是什么问题？

Answer 1

A few comments: 一些评论：

Capitalize "XML": 大写“ XML”：
var xhr = new XmlHttpRequest(); -> var xhr = new XMLHttpRequest(); -> var xhr = new XMLHttpRequest();

A variable is not a statement: 变量不是语句：
xhr.responseText; , just get rid of this line, it's like saying var a = 5; ，摆脱掉这条线，就像说var a = 5; and then a; 然后a;

You can use document.body to get the body element: 您可以使用document.body获取body元素：
var body = document.getElementsByTagName("body")[0]; -> - >
var body = document.body;

You have no variable named hxr : 您没有名为hxr变量：
hxr.send(null); -> xhr.send(null); -> xhr.send(null);

If you're following this is what you should get: 如果您遵循的是这应该得到的：

 (function () {
 var link = document.getElementsByTagName("a")[0];
 link.onclick = function () {
      var xhr = new XMLHttpRequest();
      xhr.onreadystatechange = function() {
         if ((xhr.readyState == 4) && (xhr.status == 200 || xhr.status == 304)) {
                var body = document.body;
                var p = document.createElement("p");
                var pText = document.createTextNode(xhr.responseText);
                p.appendChild(pText);
                body.appendChild(p);
            }
        };
        xhr.open("Get", "ajax.txt", true);
        xhr.send(null);
        return false;
    };
})();

If I were you I'd prefer using jQuery: 如果我是我，我宁愿使用jQuery：

$('a').first().click(function() {
    $.get('ajax.txt', function(data) {
        $(document.body).append('<p>' + data + '</p>');
    });
});

This is your entire code using jquery ;) 这是使用jquery的整个代码;）

Ajax XmlHttpRequest

问题描述

1 个解决方案

解决方案1
1 已采纳 2014-04-13 17:46:32

Ajax XmlHttpRequest

问题描述

1 个解决方案

解决方案1 1 已采纳 2014-04-13 17:46:32

解决方案1
1 已采纳 2014-04-13 17:46:32