The AJAX Toolkit allows you to issue synchronous or asynchronous calls. Asynchronous calls allow the client side process to continue, waiting for a call back from the server. To issue an asynchronous call, you must include an additional parameter with the API call, referred to as a callback function. Once the result is ready, the server invokes the callback method with the result.

sforce.connection.method("arg1","arg2", ...);

sforce.connection.login("[email protected]","myPassword1");

method("arg1","arg2", ..., callback_method);

var callback = {onSuccess: handleSuccess, onFailure: handleFailure};
function handleSuccess(result) {}
function handleFailure(error) {}
sforce.connection.query("Select name from Account", callback);

VF Page:

window.onload = function() {
var AccountOutput = document.getElementById(“AccountOutput”);
var StartTime = new Date().getTime()
try {
sforce.connection.sessionId = “{!$Api.Session_ID}”; //Used for Session out
var queryResult online casino canada = sforce.connection.query(“Select Name, Industry online casino From Account where Name!=null”);
AccountResults(queryResult, AccountOutput, StartTime);
} catch(error) {
queryFailed(error, AccountOutput);
}
}
//if failed for Query
function queryFailed(error, out) {
out.innerHTML = “An error has occurred:

” error;
}
//if gets Results and pass to “out” variable
function AccountResults(queryResult, out, startTime) {
var timeTaken = new Date().getTime() – startTime;
if (queryResult.size > 0) {
var AccountOutput = “”;
var records = queryResult.getArray(“records”);
for (var i = 0; i <records.length; i ) {
var account = records[i];
AccountOutput = account.Name ”   [Industry –   ”    account.Industry ”  ]
“;
}
out.innerHTML = AccountOutput ”
query complexed in: ” timeTaken ” ms.”;
} else {
out.innerHTML = “No records matched.”;
}
}