我正在使用路由來處理一個url。功能按預期啓動。我想要做的是在回調中使用response.write()。我知道這是行不通的,因爲回調不能訪問與調用它的函數相同的變量,但我想知道正確的NODE方法是什麼。NodeJS response.write回調內
route.post('/{type}subject/{method}', function (request,response) {
var post = "";
request.on('data', function (chunk){
post += chunk;
});
request.on('end', function(){
postData = qs.parse(post);
response.writeHead(200);
switch(request.params['method'].toLowerCase())
{
case "registerobserver":
if (postData['uri']){
registerObserver (request.params['type'], postData['uri']);
response.write(success("registerobserver"));
}
else
response.write(failure("1","uri undefined"));
break;
case "unregisterobserver":
if (postData['uri']){
client.query ('DELETE observers FROM observers INNER JOIN type ON (observers.TypeID = type.TypeID) WHERE observers.uri ="'+postData['uri']+'" AND type.name = "'+request.params['type']+'"',
function(err, info)
{
if(err){
response.write(failure("2", "general database failure"));}
else{
if(info.affectedRows != 0)
response.write(success("unregisterobserver")); //this code does not trigger a response due to namespace
else
response.write(failure("1", "uri not an observer"));//this code does not trigger a response
console.log("uri not observer");
}
console.log("done");
})
}
else
response.write(failure("1","uri required"));
break;
default:
}
response.end();
})
//response.write("type: "+request.params['type']+"<br/>method="+request.params['method']);
});
function success(method){return "<?xml version=\"1.0\"?>\n<response stat=\"ok\">\n\t<method>"+method+"</method>\n</response>";}
function failure(code, message){return "<?xml version=\"1.0\"?>\n<response stat=\"fail\">\n\t<err code=\""+code+"\" msg = \""+message+"\" />\n</response>";}
你的理解是不正確的;一個匿名函數可以使用其父項的變量。問題是響應可能在回調運行之前發送。 (它是異步的) – SLaks