mysql - Expressjs : Open view after foreach with mysql result.

Question

我正在尝试使用 mysql 查询的结果进行循环，并在该循环中执行一个新查询。循环遍历结果后，我想打开一个包含第一个和第二个查询结果的新 View 。

现在我的问题:循环工作正常，我可以打开新 View ，但是打开 View 时我只得到第一个查询的结果和第二个查询的一部分，它在运行第二个查询之前打开 View 时间。

我的代码:

 function getActivitiesDate(req,res, rows)
 {
var rows2 = [];
rows.forEach(function getoutput(item) {
    console.log("getActivitiesDate openend");
    connectionpool.getConnection(function(err, connection3) {
        console.log('Trying to connect to activities date');
        if (!err) {
            console.log('Trying to execute query for activities now'),
                connectionpool.query('SELECT * FROM CALENDAR_ACTIVITY WHERE ACTIVITY_ID =' + connection3.escape(item.ACTIVITY_ID),
                    function (err, rows2) {
                        if (err) {
                            console.error(err);
                            res.statusCode = 500;
                            res.send({
                                result: 'error',
                                err: err.code
                            });
                            connection3.release();
                            console.log('It doesnt work error 500');
                        }
                        if (rows2.length == 0) {
                            res.render('index', {title: 'Index - Calendar Activity not found'});
                        }
                        console.log('Show activities + dates');



                      //  connection3.release();
                    });
        } else {
            console.error('CONNECTION error: ', err);
            res.statusCode = 503;
            res.send({
                result: 'error',
                err: err.code
            });
            console.log('It does not work...');
        }
    });

});
console.log('This is the result of rows2Result: ');
console.log(rows2);
res.render('viewUserActivities', {activities:rows, activityDates:rows2 , title: 'Created activities'});

}

“rows”属性目前包含 2 行(这可能更多或更少，这就是我有“rows.forEach”的原因)，但我不确定如何将“rows2”的结果传递给在每个结果都通过 foreach 循环循环之后的新 View 。

任何帮助将不胜感激。我不清楚，或者您需要更多信息，请随时询问。

Answer 1

我没有足够的代表来发表评论，因此我可能会误解这个问题，但是您可以在 forEach 回调完成后渲染 View 吗？

像这样:

function getActivitiesDate(req,res, rows)
{
var rows2 = [];
rows.forEach(function getoutput(item) {
console.log("getActivitiesDate openend");
connectionpool.getConnection(function(err, connection3) {
    console.log('Trying to connect to activities date');
    if (!err) {
        console.log('Trying to execute query for activities now'),
            connectionpool.query('SELECT * FROM CALENDAR_ACTIVITY WHERE ACTIVITY_ID =' + connection3.escape(item.ACTIVITY_ID),
                function (err, rows2) {
                    if (err) {
                        console.error(err);
                        res.statusCode = 500;
                        res.send({
                            result: 'error',
                            err: err.code
                        });
                        connection3.release();
                        console.log('It doesnt work error 500');
                    }
                    else if (rows2.length == 0) {
                        res.render('index', {title: 'Index - Calendar Activity not found'});
                    } else {
                          console.log('This is the result of rows2Result: ');
                          console.log(rows2);
                        res.render('viewUserActivities', {activities:rows, activityDates:rows2 , title: 'Created activities'});
                    console.log('Show activities + dates');

                    }

                  //  connection3.release();
                });
    } else {
        console.error('CONNECTION error: ', err);
        res.statusCode = 503;
        res.send({
            result: 'error',
            err: err.code
        });
        console.log('It does not work...');
    }
});