With jquery, ajax has become quite simple.
However, for simplicity, you may not need to load a huge js plug-in such as jquery in the project.
But what should I do if I want to use ajax?
Before implementing ajax, you must create an XMLHttpRequest object.
If you cannot create a browser for this object, you need to create ActiveXObject as follows:
Var xmlHttp;
Function createxmlHttpRequest (){
If (window. ActiveXObject ){
XmlHttp = new ActiveXObject ("Microsoft. XMLHTTP ");
} Else if (window. XMLHttpRequest ){
XmlHttp = new XMLHttpRequest ();
}
1. Use the xmlHttp created above to implement the simplest ajax get request:
Function doGet (url ){
// Use encodeURI to process parameter values to prevent garbled characters.
CreatexmlHttpRequest ();
XmlHttp. open ("GET", url );
XmlHttp. send (null );
XmlHttp. onreadystatechange = function (){
If (xmlHttp. readyState = 4) & (xmlHttp. status = 200 )){
Alert ('success ');
} Else {
Alert ('fail ');
}
}
}
2. Use the xmlHttp created above to implement the simplest ajax post request:
Function doPost (url, data ){
// Use encodeURI to process parameter values to prevent garbled characters.
CreatexmlHttpRequest ();
XmlHttp. open ("POST", url );
XmlHttp. setRequestHeader ("Content-Type", "application/x-www-form-urlencoded ");
XmlHttp. send (data );
XmlHttp. onreadystatechange = function (){
If (xmlHttp. readyState = 4) & (xmlHttp. status = 200 )){
Alert ('success ');
} Else {
Alert ('fail ');
}
}
}