问题
I have a strange problem which is the passed variable to the jade is empty at the browser, it seems the passed variable is null but it isn't
the nodejs code(the whole route code):
exports.sensorsettings = function(req, res){
if (!req.session.username) {
// if false render
res.render('login', { logo: 'img/owl.png', id: 'home', brand: brand })
} else {
if(!req.query.sid) (res.redirect('/dashboard'));
// get sid information from database
db.collection('sensors').findOne({sid:req.query.sid}, function(err, result) {
console.log('this is result:' + result);
if (result) {
console.log('this is result:' + result.name);
result= JSON.stringify(result);
res.render('new-sensor-settings', { username: req.session.username, name:result.name,
ipaddress: result.ipaddress, desc: result.desc, snmpcom: result.snmpcom, snmpver: result.snmpver,
snmpport: result.snmpport, snmpifindex: result.snmpifindex, ncusername: result.ncusername,
ncport: result.ncport})
};
if (!result) res.redirect('/errors?err=db');
});
// if true redirect
res.render('new-sensor-settings', { username: req.session.username, id: 'home', brand: brand })
}
};
jade file(the whole form):
form.form-horizontal
.tab-content(style='padding: 0;')
#account-details.tab-pane
.row-fluid
.span6
.control-group
label.control-label Community
.controls
input#s_snmpcom.span10(type='text', value=snmpcom)
span.btn-action.single.glyphicons.circle_question_mark(style='margin: 0;', data-toggle='tooltip', data-placement='top', data-original-title='Specify your device Public Community name (For SNMP version 2c)')
i
.control-group
label.control-label Port Number
.controls
input#s_snmpport.input-mini(type='text', value=snmpport)
span.btn-action.single.glyphicons.circle_question_mark(style='margin: 0;', data-toggle='tooltip', data-placement='top', data-original-title='Specify your device SNMP port number, Default number is 161 ')
i
.span6
.control-group
label.control-label Version
.controls
select#s_snmpver.selectpicker.span6(data-style='btn-default', style='display: none;')
option 1
option 2c
option 3
.control-group
label.control-label IfIndex
.controls
input#s_snmpif.input-mini(type='text', value=snmpifindex)
span.btn-action.single.glyphicons.circle_question_mark(style='margin: 0;', data-toggle='tooltip', data-placement='top', data-original-title='Specify your SNMP interface index number.it could be found at interface details of your device')
i
hr.separator.bottom
.row-fluid
.span6
.control-group
label.control-label Username
.controls
input#s_ncuser.span10(type='text', value=ncusername)
span.btn-action.single.glyphicons.circle_question_mark(style='margin: 0;', data-toggle='tooltip', data-placement='top', data-original-title='Specify your device Netconf username, it could be on of defined username on your device with readonly access.')
i
.control-group
label.control-label Port Number
.controls
input#s_ncport.input-mini(type='text', value=ncport)
span.btn-action.single.glyphicons.circle_question_mark(style='margin: 0;', data-toggle='tooltip', data-placement='top', data-original-title='Specify your device ssh port number, Default number is 22 ')
i
.span6
.control-group
label.control-label password
.controls
input#s_ncpass.span10(type='password', value='')
span.btn-action.single.glyphicons.circle_question_mark(style='margin: 0;', data-toggle='tooltip', data-placement='top', data-original-title='Enter the password of Netconf username')
i
.form-actions(style='margin: 0;')
button.btn.btn-icon.btn-primary.glyphicons.circle_ok.pull-right(type='submit')
i
| Save changes
button.btn.btn-icon.btn-default.glyphicons.circle_remove.pull-right(type='button')
i
| Cancel
#account-settings.tab-pane.active
.row-fluid
.span3
strong Sensor General Settings
p.muted Configure Sensor basic settings here,all fields are required.
.span9
label(for='s_name') Name
input#s_name.span10(type='text', value=name)
span.btn-action.single.glyphicons.circle_question_mark(style='margin: 0;', data-toggle='tooltip', data-placement='top', data-original-title='Give your sensor a name so you could call it!')
i
.separator
label(for='s_ip') IP Address
input#s_ip.span10(type='text', value=ipaddress , placeholder='' )
span.btn-action.single.glyphicons.circle_question_mark(style='margin: 0;', data-toggle='tooltip', data-placement='top', data-original-title='Enter sensor IP address here')
i
.separator
label(for='s_offline') Sensor Offline
input#inputPasswordNew.span12(type='text', value='', placeholder='if your sensor is down for maintenance, change its status to offline')
.separator
label(for='s_description') Description
input#s_description.span12(type='text', value=desc)
.separator
.form-actions(style='margin: 0; padding-right: 0;')
button.btn.btn-icon.btn-primary.glyphicons.circle_ok.pull-right(type='submit')
i
| Save changes
note: everything except the username variable will not work. i tried to assign a static value for those variables (for example name:'test') but it won't work neither.
回答1:
It's hard to tell what you are trying to accomplish here but here is a starting point. The main change I made was removing the two lines
// if true redirect
res.render('new-sensor-settings', { username: req.session.username, id: 'home', brand: brand })
because those were being executed before the callback of
db.collection.findOne, and thus prevented a response from being sent when the
inner res.render was called. I am just guessing that these lines are
extraneous, perhaps a leftover from a previous iteration of the function. If
they are not accidental, please provide more information about what the function
should do.
Other minor changes I made:
Reindented to 2 spaces.
I added curly brackets around the if(!req.query.sid) statement. (it's fine to
have one-line if statements without the curly brackets, but it's less
maintainable, so my personal preference is to always add them.)
I added return in front of the statements that send a response. Since the
res.redirect and res.render statements are all placed at the end of their
respective if blocks, there is no longer any chance of two of them executing.
So the returns here aren't strictly really necessary - it's just my personal
preference to use them, making it explicit that now that the response has been
sent, no further code should be executed in this route.
I moved if(!result) into an else block attached to the previous if(result)
exports.sensorsettings = function(req, res){
if (!req.session.username) {
// if false render
return res.render('login', { logo: 'img/owl.png', id: 'home', brand: brand })
} else {
if(!req.query.sid){ (return res.redirect('/dashboard')); }
// get sid information from database
db.collection('sensors').findOne({sid:req.query.sid}, function(err, result) {
console.log('this is result:' + result);
if (result) {
console.log('this is result:' + result.name);
// Problem here too:
result= JSON.stringify(result);
// result is now a string, trying to access properties will be undefined
return res.render('new-sensor-settings', { username: req.session.username, name:result.name,
ipaddress: result.ipaddress, desc: result.desc, snmpcom: result.snmpcom, snmpver: result.snmpver,
snmpport: result.snmpport, snmpifindex: result.snmpifindex, ncusername: result.ncusername,
ncport: result.ncport})
} else {
return res.redirect('/errors?err=db');
};
});
}
};
回答2:
try this notation #{ipaddress}, works for me every time
来源：https://stackoverflow.com/questions/19401773/jade-server-side-passed-variable-is-empty-at-browser