Retrieving list of names from list of name value pairs

[JSnovice1]

I have list of paired values, and i need to get the list of just the first item:

Example:
Input: CA: San Francisco, TX:Austin, CA: San Jose, GA: Atlanta, MA: Boston
Output: CA, TX, CA, GA, MA

Can someone help me with a Javascript snippet that achieves this? I am thinking on lines of using split and join, but I am getting confused, especially because the number of attributes in the original list is not fixed.

[ZABI]

<script>
var Input='CA: San Francisco, TX:Austin, CA: San Jose, GA: Atlanta, MA: Boston';
var arr=Input.replace(/\s+/g, '').split(',');
var ext=new Array();
for (i=0;i<arr.length;i++){
ext[i]=arr[i].substring(0,2);
}
alert(ext.join(','));
</script>

hope it works for you

[rnd me]

"CA: San Francisco, TX:Austin, CA: San Jose, GA: Atlanta, MA: Boston".split(/:[\w\s]+/).join("") // == "CA, TX, CA, GA, MA"

[Troy III]

obj = {CA:"San Francisco", TX:"Austin", CA:"San Jose", GA:"Atlanta", MA:"Boston"};
Object.getOwnPropertyNames(obj);
>> ["GA", "CA", "MA", "TX"]

p.s.:
Only IE will preserve the original order, ie:
["CA"," TX", "GA", "MA"]

And you have a problem there with double entry of CA key.
You'll need to correct that.

i.e.:
CA: ["San Francisco", "San Jose"]