I have a getter to get the value from a cookie.
Now I have 2 cookies by the name shares= and by the name obligations= .
I want to make this getter only to get the values from the obligations cookie.
How do I do this? So the for splits the data into separate values and puts it in an array.
function getCookie1() {
// What do I have to add here to look only in the "obligations=" cookie?
// Because now it searches all the cookies.
var elements = document.cookie.split('=');
var obligations= elements[1].split('%');
for (var i = 0; i < obligations.length - 1; i++) {
var tmp = obligations[i].split('$');
addProduct1(tmp[0], tmp[1], tmp[2], tmp[3]);
}
}
Answer
One approach, which avoids iterating over an array, would be:
function getCookie(name) {
const value = `; ${document.cookie}`;
const parts = value.split(`; ${name}=`);
if (parts.length === 2) return parts.pop().split(';').shift();
}
Walkthrough
Splitting a string by token will produce either, an array with one string (same value), in case token does not exist in a string, or an array with two strings , in case token is found in a string .
The first (left) element is string of what was before the token, and the second one (right) is what is string of what was after the token.
(NOTE: in case string starts with a token, first element is an empty string)
Considering that cookies are stored as follows:
"{name}={value}; {name}={value}; ..."
in order to retrieve specific cookie value, we just need to get string that is after "; {name}=" and before next ";". Before we do any processing, we prepend the cookies string with "; ", so that every cookie name, including the first one, is enclosed with "; " and "=":
"; {name}={value}; {name}={value}; ..."
Now, we can first split by "; {name}=", and if token is found in a cookie string (i.e. we have two elements), we will end up with second element being a string that begins with our cookie value. Then we pull that out from an array (i.e. pop), and repeat the same process, but now with ";" as a token, but this time pulling out the left string (i.e. shift) to get the actual token value.