Develop Reference

Javascript object set to another object is undefined

For my chrome extension, I have a function called storeGroup that returns an object. However, in function storeTabsInfo, when I call storeGroup and set it equal to another object, the parts inside the object are undefined. The object is being populated correctly in storeGroup, so I'm not sure why it's undefined?
function storeTabsInfo(promptUser, group)
{
var tabGroup = {};
chrome.windows.getCurrent(function(currentWindow)
{
chrome.tabs.getAllInWindow(currentWindow.id, function(tabs)
{
/* gets each tab's name and url from an array of tabs and stores them into arrays*/
var tabName = [];
var tabUrl = [];
var tabCount = 0;
for (; tabCount < tabs.length; tabCount++)
{
tabName[tabCount] = tabs[tabCount].title;
tabUrl[tabCount] = tabs[tabCount].url;
}
tabGroup = storeGroup(promptUser, group, tabName, tabUrl, tabCount); // tabGroup does not store object correctly
console.log("tabGroup: " + tabGroup.tabName); // UNDEFINED
chrome.storage.local.set(tabGroup);
})
})
}
function storeGroup(promptUser, group, name, url, count)
{
var groupObject = {};
// current count of group
var groupCountValue = group.groupCount;
var groupName = "groupName" + groupCountValue;
groupObject[groupName] = promptUser;
var tabName = "tabName" + groupCountValue;
groupObject[tabName] = name;
var tabUrl = "tabUrl" + groupCountValue;
groupObject[tabUrl] = url;
var tabCount = "tabCount" + groupCountValue;
groupObject[tabCount] = count;
var groupCount = "groupCount" + groupCountValue;
groupObject[groupCount] = groupCountValue + 1;
// successfully shows parts of groupObject
console.log("Final group: " + groupObject[groupName] + " " + groupObject[tabName] + " " + groupObject[tabUrl] + " " + groupObject[tabCount] + " " + groupObject[groupCount]);
return groupObject;
}

As i said in the comment above you created the groupObject dict keys with the group count so you should use it again to access them or remove it, if you want to use it again although i think this isnt necessary so use:-
... ,tabGroup[tabName + group.groupCount]...
But if you want to get it easily as you wrote just write this code instead of your code:-
function storeGroup(promptUser, group, name, url, count)
{
var groupObject = {};
// current count of group
groupObject['groupName'] = promptUser;
groupObject['tabName'] = name;
groupObject['tabUrl'] = url;
groupObject['tabCount'] = count;
groupObject['groupCount'] = group.groupCount + 1;
// successfully shows parts of groupObject
console.log("Final group: " + groupObject['groupName'] +
" " + groupObject['tabName'] + " " + groupObject['tabUrl'] +
" " + groupObject['tabCount'] + " " +
groupObject['groupCount']);
return groupObject;
}

SharePoint working with lookup dropdowns and getting values

I seem to have a little trouble getting a value to be returned from a dropdown lookup field. I've got the following code that gets me the values from the list I'm doing the lookup upon:
var siteUrl = _spPageContextInfo.webServerRelativeUrl;
function getDropdownValues(tempNumTitle) {
var clientContext = new SP.ClientContext(siteUrl);
var tempDropdownValueList = clientContext.get_web().get_lists().getByTitle('Temps');
var camlQuery = new SP.CamlQuery();
camlQuery.set_viewXml('<View>' +
'<RowLimit>' +
'100' +
'</RowLimit>' +
'</View>');
this.tempQuery = tempDropdownValueList.getItems(camlQuery);
clientContext.load(tempQuery);
clientContext.executeQueryAsync(
// on success of getting Temp Values from dropdown
// match it with the tempNum entry
function (sender, args) {
var tempDropDownValues = {};
var tempEnumerator = tempQuery.getEnumerator();
while(tempEnumerator.moveNext()) {
var tempItem = tempEnumerator.get_current();
var tempTitle = tempItem.get_item('Title');
var tempId = tempItem.get_item('ID');
tempDropDownValues[tempTitle] = tempId;
}
selectTemp(tempNumTitle, tempDropdownValues)
},
// on failure
function (sender, args) {
console.info('Request failed. ' + args.get_message() + '\n' + args.get_stackTrace());
}
);
}
It performs this fine, giving me the dropdown values. It then calls the function selectTemp with the parameters of the tempNumTitle we are looking for, and the list of dropdown values retrieved. Here is the next function:
function selectTemp(tempNumTitle, tempValues) {
var clientContext = new SP.ClientContext(siteUrl);
var tempMatchValueList = clientContext.get_web().get_lists().getByTitle('Numbers-Temp');
var camlQuery = new SP.CamlQuery();
camlQuery.set_viewXml('<View>' +
'<Query>' +
'<Where>' +
'<Eq>' +
'<FieldRef Name="Title" />' +
'<Value Type="Text">' + tempNumTitle + '</Value>' +
'</Eq>' +
'</Where>' +
'</Query>' +
'</View>');
this.tempMatchValueQuery = tempMatchValueList.getItems(camlQuery);
clientContext.load(tempMatchValueQuery);
clientContext.executeQueryAsync(
// on success
function (sender, args) {
var temp = '';
tempEnumerator = tempMatchValueQuery.getEnumerator();
while(tempEnumerator.moveNext()) {
var tempItem = tempEnumerator.get_current();
temp = tempItem.get_item('Temp0');
}
},
// on failure
function (sender, args) {
console.info('Request failed. ' + args.get_message() + '\n' + args.get_stackTrace());
}
);
}
It almost gets me what I'm looking for, but I get something like this:
temp: {$1E_1: 3, $2e_1: "Temp 3"}
Where I want the value of the $2e_1, or "Temp 3". How can I get that value, without just going temp["$2e_1"]?

When accessing a lookup column or a people picker column, the column value is a complex type rather than a simple string.
You can invoke .get_lookupValue() on the returned object to get a text representation of the lookup column's value, or .get_lookupId() to get the ID number of the corresponding item in the lookup list (or in the site collection's user information list in the case of a people picker column).
So in your case, assuming "Temp0" is the internal name of a lookup column, you should be able to do this:
temp = tempItem.get_item('Temp0').get_lookupValue();

How to dynamically access object's property?

I have trouble accessing object' property in the example below. On the third line I'd like to have the number 42 replaced with the value of the variable devNumTemp, but so far I'm not successfull.
What is the proper way to do this? I've tried several options, but never getting any further than getting undefined.
function getTempDev(devNumTemp, devNumHum, id, description){
$.getJSON("http://someurl.com/DeviceNum=" + devNumTemp,function(result){
var array = result.Device_Num_42.states;
function objectFindByKey(array, key, value) {
for (var i = 0; i < array.length; i++) {
if (array[i][key] === value) {
$("#id").html(description + "<div class='right'>" + array[i].value + "°C" + " (" + someVariable + "%" + ")" + "<br></div>");
}
}
};
objectFindByKey(array, 'service', 'something');
});
};

You can acces to object's properties like this
var array = result["Device_Num_" + devNumTemp].states;
It's considered a good practice to test for field's existance before trying to access it:
var array = [];
if (result && result["Device_Num_" + devNumTemp]){
array = result["Device_Num_" + devNumTemp].states;
}
This way we prevent Null Pointer Exception type errors.

Node.js with Restler to return a value?

This is very early in my Node and JavaScript learning. Ideally, what I am attempting to do is create a small module querying a specific type of rest endpoint and returning a specific feature based on an attribute query. The module is correctly logging out the result, but I am struggling to get the .findById function to return this result. Although aware it has something to do with how the callbacks are working, I am not experienced enough to be able to sort it out yet. Any help, advice and direction towards explaning the solution is greatly appreciated.
// import modules
var restler = require('restler');
// utility for padding zeros so the queries work
function padZeros(number, size) {
var string = number + "";
while (string.length < size) string = "0" + string;
return string;
}
// create feature service object
var FeatureService = function (url, fields) {
// save the parameters
this.restEndpoint = url;
this.fields = fields;
var self = this;
this.findById = function (idField, value, padZeroLength) {
var options = {
query: {
where: idField + '=\'' + padZeros(value, padZeroLength) + '\'',
outFields: this.fields,
f: "pjson"
},
parsers: 'parsers.json'
};
var url = this.restEndpoint + '/query';
restler.get(url, options).on('complete', function(result){
if (result instanceof Error){
console.log('Error:', result.message);
} else {
console.log(result); // this log result works
self.feature = JSON.parse(result);
}
});
return self.feature;
};
};
var restEndpoint = 'http://services.arcgis.com/SgB3dZDkkUxpEHxu/ArcGIS/rest/services/aw_accesses_20140712b/FeatureServer/1';
var fields = 'nameRiver,nameSection,nameSectionCommon,difficulty,diffMax';
var putins = new FeatureService(restEndpoint, fields);
var feature = putins.findById('awid_string', 1143, 8);
console.log(feature); // this log result does not
//console.log('River: ' + feature.attributes.nameRiver);
//console.log('Section: ' + feature.attributes.nameSection + ' (' + feature.attributes.nameSectionCommon + ')');
//console.log('Difficulty: ' + feature.attributes.difficulty);

So, I sorted out how to insert a callback from a previous thread. It appears it is just passed in as a variable and called with expected parameters. However, I now wonder if there is a better way to accept parameters, possibly in the form of options. Any advice in this regard?
// import modules
var restler = require('restler');
// utility for padding zeros so the queries work
function padZeros(number, size) {
var string = number + "";
while (string.length < size) string = "0" + string;
return string;
}
// create feature service object
var FeatureService = function (url, fields) {
// save the parameters
this.restEndpoint = url;
this.fields = fields;
var self = this;
// find and return single feature by a unique value
this.findById = function (idField, value, padZeroLength, callback) {
// query options for
var options = {
query: {
where: idField + '=\'' + padZeros(value, padZeroLength) + '\'',
outFields: this.fields,
f: "pjson"
},
parsers: 'parsers.json'
};
var url = this.restEndpoint + '/query';
restler.get(url, options)
.on('success', function(data, response){
var dataObj = JSON.parse(data).features[0];
console.log(dataObj);
callback(dataObj);
})
.on('fail', function(data, response){
console.log('Error:', data.message);
});
return self.feature;
};
};
var restEndpoint = 'http://services.arcgis.com/SgB3dZDkkUxpEHxu/ArcGIS/rest/services/aw_accesses_20140712b/FeatureServer/1';
var fields = 'nameRiver,nameSection,nameSectionCommon,difficulty,diffMax';
var putins = new FeatureService(restEndpoint, fields);
putins.findById('awid_string', 1143, 8, function(dataObject){
console.log('River: ' + dataObject.attributes.nameRiver);
console.log('Section: ' + dataObject.attributes.nameSection + ' (' + dataObject.attributes.nameSectionCommon + ')');
console.log('Difficulty: ' + dataObject.attributes.difficulty);
});

Function Scope issue when declaring an array of objects

This is the code that I currently have, one problem that is happening is I cannot use test() because presets[index].name and value are not visible outside of their function scope, how should I declare my array of objects in the global scope in order for me to be able to access these two variables in other functions?
var presets = [];
var index;
function CreatePresetArray(AMib, AVar) {
var parentpresetStringOID = snmp.getOID(AMib, AVar);
var presetStringOID = parentpresetStringOID;
parentpresetStringOID = parentpresetStringOID.substring(0, parentpresetStringOID.length - 2);
log.error("parentpresetStringOID is " + parentpresetStringOID);
var presetswitches = {};
for (var i = 1; i < 41; i++) {
presets.push(presetswitches);
try {
log.error("presetStringOID before getNextVB= " + presetStringOID);
vb = snmp.getNextVB(presetStringOID);
presetStringOID = vb.oid;
log.error("presetStringOID after getnextVB= " + presetStringOID);
var presetStringVal = snmp.get(presetStringOID);
log.error("presetStringVal= " + presetStringVal);
index = i - 1;
presets[index].name = presetStringOID;
presets[index].value = presetStringVal;
log.error("preset array's OID at position [" + index + "] is" + presets[index].name + " and the value stored is " + presets[index].value);
//log.error("presets Array value ["+index+"] = "+presets[index].configs);
if (presetStringOID.indexOf(parentpresetStringOID) != 0) {
break;
}
} catch (ie) {
log.error("couldn't load preset array " + index);
};
};
}
CreatePresetArray(presetMib, "presetString");
function test() {
for (i = 1; i < 41; i++) {
log.error("test" + presets[index].name + " " + presets[index].value);
};
}
test();

The for loop in your function test iterates over i but uses index inside the loop. Perhaps you meant to use
for (i = 0; i < 40; i++) { // 1 lower as you were using `index = i - 1` before
log.error("test" + presets[i].name + " " + presets[i].value);
}
Re-wrote your code. I don't think I made that much by way of change. If this doesn't clear up your problem, consider: Is the catch happening each iteration? Is the problem actually coming from a different method which is only visible here? Also, consider logging the whole presets Array when debugging to see what it looks like.
var presets = [];
function CreatePresetArray(AMib, AVar) {
var parentPresetOID, presetOID, presetValue, preset, vb, i;
parentPresetOID = snmp.getOID(AMib, AVar);
presetOID = parentPresetOID; // initial
parentPresetOID = parentPresetOID.substring(0, parentPresetOID.length - 2);
log.error("parentPresetOID is " + parentPresetOID);
presets = []; // empty array in case not already empty
for (i = 0; i < 40; ++i) {
try {
preset = {}; // new object
// new presetOID
vb = snmp.getNextVB(presetOID);
presetOID = vb.oid;
log.error("presetOID after getnextVB= " + presetOID);
// new value
presetValue = snmp.get(presetOID);
log.error("presetValue= " + presetValue);
// append data to object
preset.name = presetOID;
preset.value = presetValue;
// append object to array
presets.push(preset);
// more logging
log.error(
"preset array's OID at position [" + i + "]" +
" is" + presets[i].name + " and " +
"the value stored is " + presets[i].value
);
if (presetOID.indexOf(parentPresetOID) !== 0) {
break;
}
} catch (ie) {
log.error("couldn't load preset array " + i);
if (presets.length !== i + 1) { // enter dummy for failed item
presets.push(null);
}
}
}
}

Two options come to mind immediately:
you could pass the preset array as a argument to test().
You could put both CreatePresetArray() and test() inside a wrapper function and declare preset array at the top of your wrapper. That would give them both access to the variable.
It's generally considered Bad Form to declare globals if it can be avoided. Pollutes the namespace.