I want to populate a series of strings (beijingString, belingString etc) with values from an array ('contentStrings'); so as not to have to do:
beijingString = 'five strings';
berlinString = 'similar but different five strings';
bronxString = 'also similar but different five strings';
buenosairesString = 'similar again but subtly different five strings';
In the end I have 40 such strings to populate.
I tried putting the cities' string variable names into a second array ('cities') and looping through, assigning indexed values.
But it does not work.
Do I have to 'reference' (?) each variable as an element of the 'cities' array in some way, please?
TIA!
Full code snippet:
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<script>
var beijingContentString = '';
var berlinContentString = '';
var bronxContentString = '';
var buenos_airesContentString = '';
var contentStrings = [
['http://www.beijing.com',
'Beijing title',
'<img src="./images/beijing.jpg">',
'Beijing caption',
'Beijing description'
],
['http://www.berlin.com',
'Berlin title',
'<img src="./images/berlin.jpg">',
'Berlin caption',
'Berlin description'
],
['http://www.bronx.com',
'Bronx title',
'<img src="./images/Bronx.jpg">',
'Bronx caption',
'Bronx description'
],
['http://www.buenosaires.com',
'Buenos Aires title',
'<img src="./images/Buenos Aires.jpg">',
'Buenos Aires caption',
'Buenos Aires description'
]
];
var beijingString = '';
var berlinString = '';
var bronxString = '';
var bueonosairesString = '';
alert ('before: ' + beijingString);
alert ('before: ' + berlinString);
alert ('before: ' + bronxString);
alert ('before: ' + bueonosairesString);
var cities = [beijingString, berlinString, bronxString, bueonosairesString];
var contentArrayLoop = 0;
for (contentArrayLoop = 0; contentArrayLoop < 4; contentArrayLoop++) {
cities[contentArrayLoop]=
contentStrings[contentArrayLoop][0] +
contentStrings[contentArrayLoop][1] +
contentStrings[contentArrayLoop][2] +
contentStrings[contentArrayLoop][3] +
contentStrings[contentArrayLoop][4]
;
alert(cities[contentArrayLoop]);
};
alert ('after: ' + beijingString);
alert ('after: ' + berlinString);
alert ('after: ' + bronxString);
alert ('after: ' + bueonosairesString);
</script>
</body>
</html>
-
Could you turn this into an object?Brett Weber– Brett Weber2014年09月05日 00:49:50 +00:00Commented Sep 5, 2014 at 0:49
3 Answers 3
A far better example is here: http://jsfiddle.net/L1dpt0bs/1/
You don't need to use any static array for cities.
var contentArrayLoop = 0;
for (contentArrayLoop = 0; contentArrayLoop < 4; contentArrayLoop++) {
var city = contentStrings[contentArrayLoop][1]
city = city.substring(0, city.indexOf(' '));
window[city + 'string'] = contentStrings[contentArrayLoop].join('');
};
alert ('after: ' + Beijingstring);
alert ('after: ' + Berlinstring);
alert ('after: ' + Bronxstring);
alert ('after: ' + Bueonosairesstring);
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Comments
This isn't all of your data, but this is a format you could use to access the information easily:
var oContentObj =
{
buenos_airesContent :
{
url : 'http://www.buenosaires.com',
title : 'Buenos Aires title',
img : '<img src="./images/Buenos Aires.jpg">',
caption : 'Buenos Aires caption',
dsc : 'Buenos Aires description'
}
}
To loop through the properties of that object, use a for.. in loop :
for (var oCity in oContentObj)
{
// now you have a loop of the cities.. do stuff
for (var oProp in oCity)
{
// Now you have the properties of the city.. do more stuff
}
}
Or you could call the properties directly
oContentObj["CityName"]["CityProp"];
// or
oContentObj.CityName.CityProp;
And for a bigger picture on handling that data on the client,
that object can become much more than a container.
It can control handling that data as well. Containing, displaying, modifying and transporting if needed. :D
answered Sep 5, 2014 at 1:00
Brett Weber
1,90718 silver badges23 bronze badges
3 Comments
marksealey
Brett, Thanks! I did think about an object like that. Could I still loop through data to populate successive objects without lines and lines of individual assignments?
Brett Weber
Yeah, but with this object you can loop through the items in it if you need to by doing a for.. in loop or you can call properties by nae if you need to do that. I like it better than an array, anyday. At that point you can even start putting functions on the object and making it control itself, giving you the data you want and modifying or displaying it even return you a list of properties or values.
You can use concept of dynamic variable
var cities = ['beijing', 'berlin', 'bronx', 'bueonosaires'];
var contentArrayLoop = 0;
for (contentArrayLoop = 0; contentArrayLoop < 4; contentArrayLoop++) {
window[cities[contentArrayLoop] + 'string'] =
contentStrings[contentArrayLoop][0] +
contentStrings[contentArrayLoop][1] +
contentStrings[contentArrayLoop][2] +
contentStrings[contentArrayLoop][3] +
contentStrings[contentArrayLoop][4]
;
};
alert ('after: ' + beijingstring);
alert ('after: ' + berlinstring);
alert ('after: ' + bronxstring);
alert ('after: ' + bueonosairesstring);
Full code is here:
GitaarLAB
14.7k12 gold badges62 silver badges83 bronze badges
13 Comments
marksealey
masum7, Thanks! In each of the two examples you kindly give, is it possible to avoid the window[] part: I just want to populate those variables - and not really display them... that comes later in my code?
masum7
For assignment you need to use that.. But when you will use it you don't need to use window.. this is just one time..
masum7
Also check the other answer that I have given.. the total dynamic one. That one is better
marksealey
masum7, thanks! I do get this error ReferenceError: BueonosaireString is not defined. Am I right that the line with the city =... assignment is reading strings from the contentStrings array to build those variable names?
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