我怎么能使AJAX调用没有jQuery?

如何使用JavaScript进行AJAX调用，而不使用jQuery?

当前回答

您可以使用以下函数:

function callAjax(url, callback){
    var xmlhttp;
    // compatible with IE7+, Firefox, Chrome, Opera, Safari
    xmlhttp = new XMLHttpRequest();
    xmlhttp.onreadystatechange = function(){
        if (xmlhttp.readyState == 4 && xmlhttp.status == 200){
            callback(xmlhttp.responseText);
        }
    }
    xmlhttp.open("GET", url, true);
    xmlhttp.send();
}

你可以在这些链接上尝试类似的解决方案:

https://www.w3schools.com/xml/tryit.asp?filename=tryajax_first https://www.w3schools.com/xml/tryit.asp?filename=tryajax_callback

2013-08-19 22:52:36

其他回答

xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
        alert(this.responseText);
    }
};
xhttp.open("GET", "ajax_info.txt", true);
xhttp.send();

2011-12-19 20:30:30

使用“vanilla”(普通)JavaScript:

function loadXMLDoc() {
    var xmlhttp = new XMLHttpRequest();

    xmlhttp.onreadystatechange = function() {
        if (xmlhttp.readyState == XMLHttpRequest.DONE) { // XMLHttpRequest.DONE == 4
           if (xmlhttp.status == 200) {
               document.getElementById("myDiv").innerHTML = xmlhttp.responseText;
           }
           else if (xmlhttp.status == 400) {
              alert('There was an error 400');
           }
           else {
               alert('something else other than 200 was returned');
           }
        }
    };

    xmlhttp.open("GET", "ajax_info.txt", true);
    xmlhttp.send();
}

jQuery:

$.ajax({
    url: "test.html",
    context: document.body,
    success: function() {
      $(this).addClass("done");
    }
});

2011-12-19 20:30:43

下面的几个例子的一个小组合，创造了这个简单的作品:

function ajax(url, method, data, async)
{
    method = typeof method !== 'undefined' ? method : 'GET';
    async = typeof async !== 'undefined' ? async : false;

    if (window.XMLHttpRequest)
    {
        var xhReq = new XMLHttpRequest();
    }
    else
    {
        var xhReq = new ActiveXObject("Microsoft.XMLHTTP");
    }


    if (method == 'POST')
    {
        xhReq.open(method, url, async);
        xhReq.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        xhReq.setRequestHeader("X-Requested-With", "XMLHttpRequest");
        xhReq.send(data);
    }
    else
    {
        if(typeof data !== 'undefined' && data !== null)
        {
            url = url+'?'+data;
        }
        xhReq.open(method, url, async);
        xhReq.setRequestHeader("X-Requested-With", "XMLHttpRequest");
        xhReq.send(null);
    }
    //var serverResponse = xhReq.responseText;
    //alert(serverResponse);
}

// Example usage below (using a string query):

ajax('http://www.google.com');
ajax('http://www.google.com', 'POST', 'q=test');

或者如果你的参数是object(s) -轻微的额外代码调整:

var parameters = {
    q: 'test'
}

var query = [];
for (var key in parameters)
{
    query.push(encodeURIComponent(key) + '=' + encodeURIComponent(parameters[key]));
}

ajax('http://www.google.com', 'POST', query.join('&'));

两者都应该完全兼容浏览器+版本。

2014-02-24 20:03:46

现在在现代浏览器中有一个更好的本机Fetch API可用。fetch()方法允许您发出web请求。例如，从/get-data请求一些JSON:

let options = {
  method: 'GET',      
  headers: {}
};

fetch('/get-data', options)
.then(response => response.json())
.then(body => {
  // Do something with body
});

更多细节请参见MDN Web Docs: Using Fetch API。

2015-08-12 22:01:47

<html>
  <script>
    var xmlDoc = null ;

  function load() {
    if (typeof window.ActiveXObject != 'undefined' ) {
      xmlDoc = new ActiveXObject("Microsoft.XMLHTTP");
      xmlDoc.onreadystatechange = process ;
    }
    else {
      xmlDoc = new XMLHttpRequest();
      xmlDoc.onload = process ;
    }
    xmlDoc.open( "GET", "background.html", true );
    xmlDoc.send( null );
  }

  function process() {
    if ( xmlDoc.readyState != 4 ) return ;
    document.getElementById("output").value = xmlDoc.responseText ;
  }

  function empty() {
    document.getElementById("output").value = '<empty>' ;
  }
</script>

<body>
  <textarea id="output" cols='70' rows='40'><empty></textarea>
  <br></br>
  <button onclick="load()">Load</button> &nbsp;
  <button onclick="empty()">Clear</button>
</body>
</html>

2011-12-19 20:31:20

我怎么能使AJAX调用没有jQuery?

推荐文章

最新文章

标签