PHP微信开发入门（一）

<?php
//如果接收到验证信息则调用valid()函数进行验证
if (isset ( $_GET ['echostr'] )) {
	valid ();
} else {
        //如果接收到的是微信客户端的消息则实例化回复类将OPENID传递给回复类的responseMsg()方法.
	@$Wechart = new Answer();
	@$openid = $_GET ['openid'];
	@$Wechart->responseMsg ( $openid );
	}



//验证TOKEN后输出验证
function valid() {
	$echoStr = $_GET ["echostr"];
	if (checkSignature ()) {
		echo $echoStr;
		exit ();
	}
}
//验证TOKEN算法
function checkSignature() {
	if (! defined ( "TOKEN" )) {
		throw new Exception ( 'TOKEN is not defined!' );
	}
	$signature = $_GET ["signature"];
	$timestamp = $_GET ["timestamp"];
	$nonce = $_GET ["nonce"];
	$token = TOKEN;
	$tmpArr = array (
			$token,
			$timestamp,
			$nonce 
	);
	sort ( $tmpArr, SORT_STRING );
	$tmpStr = implode ( $tmpArr );
	$tmpStr = sha1 ( $tmpStr );
	
	if ($tmpStr == $signature) {
		return true;
	} else {
		return false;
	}
}
?>