Page 158 - CITS - Computer Software Application -TT

COMPUTER SOFTWARE APPLICATION - CITS

A Function to Check a Cookie
Last, we create the function that checks if a cookie is set.
If the cookie is set it will display a greeting.
If the cookie is not set, it will display a prompt box, asking for the name of the user, and stores the username
cookie for 365 days, by calling the setCookie function:
Example
function checkCookie() {
let username = getCookie(“username”);
if (username != “”) {

alert(“Welcome again “ + username);
} else {
username = prompt(“Please enter your name:”, “”);
if (username != “” && username != null) {

setCookie(“username”, username, 365);
}
}
}
All Together Now
Example

function setCookie(cname, cvalue, exdays) {
const d = new Date();
d.setTime(d.getTime() + (exdays * 24 * 60 * 60 * 1000));
let expires = “expires=”+d.toUTCString();

document.cookie = cname + “=” + cvalue + “;” + expires + “;path=/”;
}
function getCookie(cname) {
let name = cname + “=”;
let ca = document.cookie.split(‘;’);

for(let i = 0; i < ca.length; i++) {
let c = ca[i];
while (c.charAt(0) == ‘ ‘) {
c = c.substring(1);

}
if (c.indexOf(name) == 0) {
return c.substring(name.length, c.length);
}
}
return “”;

}

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CITS : IT&ITES - Computer Software Application - Lesson 37 - 46