我读了this并尝试实现我的功能,以便数据不会变回,但它对我不起作用。
我有一个对象数组,我将它们一个一个地发送到另一个函数,以添加数据。
queries.first(finalObject.sectionProjects[i]);
对于每一个sectionProjects
,都有一个变量achievements
,带有一个空数组。
在将每个 sectionProject 发送到 queries.first
函数后,我重新分配成就,
finalObject.sectionProjects[i].achievements = something else
当我从 queries.first 函数返回时,我丢失了我添加的数据。 我做错了什么吗?
函数如下:
module.exports = {
first:function(aProject) {
// Latest achievements
var query =
" SELECT ta.description, ta.remarks, ta.expectedECD " +
" FROM project pr, task ta, milestone mi " +
" WHERE pr.ID = mi.project_ID AND mi.ID = ta.milestone_ID " +
" AND ta.achived = ta.percent AND pr.ID = " + aProject.project_id +
" ORDER BY pr.expectedECD " +
" LIMIT 5;"
;
var stringified = null;
pmdb.getConnection(function(err, connection){
connection.query(query, function(err, rows){
if(err) {
throw err;
}else{
var jsonRows = [];
for( var i in rows) {
stringified = JSON.stringify(rows[i]);
jsonRows.push(JSON.parse(stringified));
}
connection.release();
aProject.achievements = jsonRows;
upcomingTasks(aProject);
}
});
});
}
}
这是 pmdb.js:
var mysql = require("mysql");
var con = mysql.createPool({
host: "localhost",
user: "user",
password: "password",
database: "database"
});
module.exports = con;
这是调用查询的主要函数。首先:
// ...Code...
//Number of section projects
var len = jsonRows.length;
console.log("Number of section projects: " + len);
var internal_counter = 0;
function callbackFun(i){
(finalObject.sectionProjects[i]).achievements = [];
queries.first(finalObject.sectionProjects[i]);
if(++internal_counter === len) {
response.json(finalObject);
}
}
var funcs = [];
for (var i = 0; i < len; i++) {
funcs[i] = callbackFun.bind(this, i);
}
for (var j = 0; j < len; j++) {
funcs[j]();
}
最佳答案
阅读That回答两次。对象充当标量原始属性的包装器。您正在将对象传递给“queries.first”函数。
针对示例代码进行了编辑
pmdb.getConnection(function(err, connection){
connection.query(query, function(err, rows){
if(err) {
throw err;
}else{
var jsonRows = [];
for( var i in rows) {
stringified = JSON.stringify(rows[i]);
jsonRows.push(JSON.parse(stringified));
}
connection.release();
aProject.achievements = jsonRows;
upcomingTasks(aProject)
}
});
});
这不是问题。像这样改变它。 “upcomingTasks”不是回调函数。在一个Project中分配成就后执行
关于Javascript 通过引用调用不起作用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/36256817/