JSON: retrieving data from http
I am new in JSON. This is the code that I make an attempt to retrieve data from http Json. But it doesn't display anything when I run it
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<script type="text/javascript">
function ajaxRequest(){
var activexmodes=["Msxml2.XMLHTTP", "Microsoft.XMLHTTP"] //activeX versions to check for in IE
if (window.ActiveXObject){ //Test for support for ActiveXObject in IE first (as XMLHttpRequest in IE7 is broken)
for (var i=0; i<activexmodes.length; i++){
try{
return new ActiveXObject(activexmodes[i])
}
catch(e){
//suppress error
}
}
}
else if (window.XMLHttpRequest) // if Mozilla, Safari etc
return new XMLHttpRequest()
else
return false
}
</script>
<title>Retrieving Json FILE</title>
</head>
<body>
<span>Demo:</span>
<div id="result"></div>
<script type="text/javascript">
var mygetrequest=new ajaxRequest()
mygetrequest.onreadystatechange=function(){
if (mygetrequest.readyState==4){
if (mygetrequest.status==200 || window.location.href.indexOf("http")==-1){
var jsondata=eval("("+mygetrequest.responseText+")") //retrieve result as an JavaScript object
var rssentries=jsondata.items
var output='<ul>'
for (var i=0; i<rssentries.length; i++){
output+='<li>'
output+='<a href="'+rssentries[i].link+'">'
output+=rssentries[i].title+'</a>'
output+='</li>'
}
output+='</ul>'
document.getElementById("result").innerHTML=output
alert("it is running")
}
else{
alert("An error has occured making the request")
}
}
}
mygetrequest.open("GET", "javascr开发者_JS百科iptkit.json", true)
mygetrequest.send(null)
</script>
</body>
</html>
Thanks for your help
If you want to do this:
new ajaxRequest('http://breathecast.com/lewis/xml_json.php?format=json')
... you must actually use the argument:
function ajaxRequest(url){
// Do something with URL
}
Compare with what you have, which is basically:
function ajaxRequest(){
// URL is never used
}
If you enable the code you commented out:
mygetrequest.open("GET", "http://breathecast.com/lewis/xml_json.php?format=json", true)
mygetrequest.send(null)
... you'll see your script is finally doing something. In my case, I get the An error has occured making the request alert because my test page is not located at http://breathecast.com/ and you cannot use XMLHttpRequest to fetch data from other domains.
加载中,请稍侯......
精彩评论