Develop Reference

Extracting a string from a response text

I'm trying to extract just the response from the following response
"{"Message":"Looks like you need to login"}"
I tried to stringyfy it as follows
var response = "{"Message":"Looks like you need to login"}";
var json_response = JSON.stringify(response);
But my response ends up looking something like this.
"{\"Message\":\"Looks like you need to login\"}"
Any ideas on why this is happening? and how I can extract just the message by doing something like
json_response.Message perhaps?

You need to use JSON.parse():
var str = "{\"Message\":\"Looks like you need to login\"}";
var json = JSON.parse(str);
console.log(json.Message);

You need to use parse() method of json which is very useful. So keep using that it is very light weighted.
Here is my answer :
var myString = "{\"Message\":\"Looks like you need to login\"}";
var parsedJson = JSON.parse(myString);
alert(parsedJson.Message);

Try this:
var response = { Message: "Looks like you need to login" } ;
var json_response = JSON.stringify( response ) ;

Capturing variable names from a select

In the back end I have written some code that reads through a file and outputs to a list of JavaScript arrays for example, the page will see:
<script>
var peanuts = ["1","s","g","3","n"];
var cashewNuts = ["d","a","f","d","n"];
var PecanNuts = ["6","m","3","x","m"];
var BrazilNuts = ["j","n","7","v","s"];
var goingNuts = ["a","e","7","m","y"];
</script>
I then want to use an array based on the value of a somewhere else in that page.
So for example:
if($('select').val()===0){
alert(firstArray[1]);
}
My issue is that the variable names are decided on what is contained in the read file, I can't know this information. Is there a way to say for example
//collect the value from the select and assign it to a var
var varN = $('select').val();
//then collect another variable that has the variable name that
//equals the value of the 'varN'
I know this seems horrendous but unfortunately based on what I need to do, it is what I need to do :(

Yes. If for example your vars are in the global scope, you can do
var val = window[varN][0]; to get peanuts:1
If you do
var nuts = {
peanuts : ["1","s","g","3","n"],
cashewNuts : ["d","a","f","d","n"],
PecanNuts : ["6","m","3","x","m"],
BrazilNuts : ["j","n","7","v","s"],
goingNuts : ["a","e","7","m","y"]
}
then you can use
var val = nuts[varN][0];

If the variables are declared directly in <script>, you can use window[varN].

JS How to include a variable in a path?

The following variable contains a string that is a path to an image.
iconBlue.image = 'http://www.site.com/icon1.jpg';
How can include a variable in this path? Let me explain more detailed. Lets say there are many icons in a folder icon1.jpg icon2.jpg etc. I have a variable named iconspec that depending on its value (1 or 2 or 3 etc) points to the icon I must use.
How can i include variable iconspec in the path?
iconBlue.image='http://www.site.com/icon"iconspec".jpg
Something like this i guess but with correct syntax.

You just need to put it like a simple string with variable.
In your case, you should do this:
iconBlue.image = 'http://www.site.com/icon'+iconspec+'.jpg';
The + operator is like the . in PHP, it merge string.

iconBlue.image='http://www.site.com/icon'+iconspec+'.jpg';

To take a little different route, you could encapsulate the concatenation in a function and make it a bit more reusable:
var icon = function(){
this.path = '';
this.imageName = '';
this.imagePath = function() { return this.path + '/' + this.imageName };
};
var iconBlue = new icon(),
iconRed = new icon();
iconBlue.path = "c:\\stuff";
iconBlue.imageName = "icon1.jpg";
iconRed.path="c:\\morestuff";
iconRed.imageName = "icon2.jpg";
alert(iconBlue.imagePath());
alert(iconRed.imagePath());

The simplest solution is to use the + to concatenate the variable to the string:
var name = 'sachleen';
var result = 'my name is ' + name;
Output: my name is sachleen
There are a couple of more powerful options available as well.
JavaScript sprintf() is a sprintf implementation for JS.
string.format in JS

JSON conversion issue

I am trying (in Javascript an Coldfusion) to convert:
{"val1":"member","val2":"book","val3":"journal","val4":"new_member","val5":"cds"},
Into this:
{ member,book,journal,new_member,cds}
Notice that I am trying to eliminate quotes.
Is it possible to achieve this? How can I do it?

Ok, so this:
{"val1":"member","val2":"book","val3":"journal","val4":"new_member","val5":"cds"}
is JSON.
To convert to a CF struct, you'd go like this:
myStruct = deserializeJSON('{"val1":"member","val2":"book","val3":"journal","val4":"new_member","val5":"cds"}');
(Note my examples assume we're operating within a <CFSCRIPT> block.)
Now you've got a simple struct with key/value pairs. But you want a list of the values. So let's make an empty string, then append all the struct values to it:
myList = "";
for (k IN myStruct) {
myList = listAppend(myList,myStruct[k]);
}
Boom. myList should now be "member,book,journal,new_member,cds"
Wrap it in curly braces if you really want to.
myList = "{"&myList&"}";

First of all, I have to thank you for your replies. But some of you have to be more polite with newbies.
var tata = {"val1":"member","val2":"book","val3":"journal","val4":"new_member","val5":"cds"}
var arr=[]
for (var i in tata) {
arr.push(tata[i])
};
console.log(arr);
wrd = new Array(arr)
var joinwrd = wrd.join(",");
console.log('{' + joinwrd + '}');

remove specific text from variable - jquery

I have a variable in my script containing data test/test1. The part test/ is already stored in another variable. I want to remove test/ from the previous variable and want to store remaining part in another variable. how can I do this??
Thanks in advance...:)
blasteralfred

In your case, x/y:
var success = myString.split('/')[1]
You split the string by /, giving you ['x', 'y']. Then, you only need to target the second element (zero-indexed of course.)
Edit: For a more general case, "notWantedwanted":
var success = myString.replace(notWantedString, '');
Where notWantedString is equal to what you want to get rid of; in this particular case, "notWanted".

If your requirement is as straightforward as it sounds from your description, then this will do it:
var a = "test/test1";
var result = a.split("/")[1];
If your prefix is always the same (test/) and you want to just strip that, then:
var result = a.substring(5);
And if your prefix varies but is always terminated with a /, then:
var result = a.substring(a.indexOf("/") + 1);

To split at the first occurence of "/":
var oldstring = "test/test1";
var newstring = oldstring.substring(oldstring.indexOf("/")+1);
There are many other ways to do this, the other answers work fine too.

Have your pick:
JavaScript replace() function.
var data = "test/test1";
data = data.replace(/data/gi, 'test/');
Or:
var data = "test/test1";
var dataArray = data.split('/');
var data1 = dataArray[0];
var data2 = dataArray[1];