问题
We are creating a web service in Azure service using node.js to retrieve data from SQL db. We are using ClearDB to do the same.
While retriving the data its not comming in a proper JSON format. How can we convert the result sql object to JSON string.
Below is my code.
app.get('/android', function(request, response) {
pool.getConnection(function(err, connection) {
if(err) { handleErrorResponse(err, response); return; }
var sql = "select projectname from taggedemployee where empname='test@hotmail.com' and tagflag='accepted'"
connection.query(sql, {}, function(err, results) {
connection.release(); // always put connection back in pool after last query
if(err) { handleErrorResponse(err, response); return; }
var proj = JSON.stringify(results);
console.log(proj);
console.log(proj[0].projectname);
for(var myKey in proj) {
console.log("key:"+ myKey+", value:"+proj[myKey]);
}
response.setHeader('Content-Type', 'application/json');
response.status(200).send(JSON.stringify(results) );
});
});
});
I cant manipulate the JSON string the returning string is
[{projectname: "Dominos"}]
I tried JSON.stringify but no luck. Please help me to fix this issue
回答1:
You don't need JSON.stringify() actually. results is already your javascript object, which represents array of json objects. Just use
console.log(results[0].projectname);
回答2:
The JavaScript Object or Array is JSON, and you need to convert a JSON string to a JavaScript Object thru the function eval or JSON.parse. Please refer to http://www.json.org/js.html.
回答3:
The response from the SQL service is JSON - as you have shown. You need to use JSON.parse() to parse the JSON into an object. Something like:
app.get('/android', function(request, response) {
pool.getConnection(function(err, connection) {
if(err) { handleErrorResponse(err, response); return; }
var sql = "select projectname from taggedemployee where empname='test@hotmail.com' and tagflag='accepted'"
connection.query(sql, {}, function(err, results) {
connection.release(); // always put connection back in pool after last query
if(err) { handleErrorResponse(err, response); return; }
var proj = JSON.parse(response);
console.log(proj);
response.setHeader('Content-Type', 'application/json');
response.status(200).send(results);
});
});
});
JSON.stringify is used to convert an object into a JSON string. JSON.parse is used to convert a JSON string into an object.
来源：https://stackoverflow.com/questions/33797867/convert-sql-object-to-valid-json-string-in-node-js-azure