Passing a return value
Please help, I have been looking at this all day and I know there must be a simple fix!
How do I pass results back to textService so that I can make a call such as textResult = textService(text to pass in);
I don't want to use a global variable if I can avoid it. This is the code
function textService(text){
req.open("GET", "http://....?text="+text, true);
req.onload = showResults;
req.send(null);
}
function showResults() {
results = req.responseXML开发者_Go百科.getElementsByTagName("Result");
}
Thank you in advance
function textService(text){
// set flag to false for sync requests
req.open("GET", "http://...?text="+text, false);
req.send(null);
// browser will be stalled till request is complete.
if(req.status == 200 && req.readyState == 4) {
return req.responseXML.getElementsByTagName("Result");
} else {
return 'request failed';
}
}
// javascript will stall till request is complete.
var results = textService('someText');
Note, making synchronous request can be harmful, if a request fails, it might stall the browser indefinatly. It's better to do it asynchronously.
function textService(text, callback){
// async is true by default, no need to pass 3rd param.
req.open("GET", "http://...?text="+text);
req.send(null);
req.onreadystatechange = function(){
if(this.readyState == 4 || this.status == 200) {
callback(this.responseXML);
}
}
}
textService('someText', function(xml){
// do stuff with XML.
});
Just need switch your coding mind to async programming ;)
You can use this
function showResults() {
results = this.responseXML.getElementsByTagName("Result");
}
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