我想從onreadystatechange返回一個變量,似乎有問題的範圍。即使我設置了全局變量,當試圖在事後檢索我的變量時,它的未定義。不太確定我做錯了什麼。在過去的三年裏,我還沒有用Javascript做過多的工作。從onreadystatechange返回變量
var lat;
var lon;
window.onload = function dosomething(){
var myRequst = new XMLHttpRequest();
var url = "http://www.instamapper.com/api?action=getPositions&key=584014439054448247";
myRequst.open('get', url);
myRequst.onreadystatechange = function(){
if ((myRequst.readyState == 4) && (myRequst.status == 200)){
//alert(myRequst.responseText);
var data = myRequst.responseText;
collected=data.split(","); //parses the data delimited by comma and put data into array
lat = collected[4];
lon = collected[5];
document.write("latitude "+lat+"<BR>\n");
document.write("latitude "+lon+"<BR>\n");
}
}
myRequst.send(null);
}
document.write(lat);
任何幫助或建議將不勝感激。