February 20, 2000 - A Name Tracker | WebReference

February 20, 2000 - A Name Tracker

Yehuda Shiran February 20, 2000
A Name Tracker
Tips: February 2000

Yehuda Shiran, Ph.D.
Doc JavaScript

The following script asks the user for his or her name, and "remembers" the input. It then welcomes the user each time he or she accesses the page, without asking again for the name. It's useful to provide a button, or another mechanism, to let the user change the name (in case several people are using the same machine, or in case the user has mistyped his or her name).

// create an instance of the Date object
var now = new Date();
// fix the bug in Navigator 2.0, Macintosh
// cookie expires in one year (actually, 365 days)
// 365 days in a year
// 24 hours in a day
// 60 minutes in an hour
// 60 seconds in a minute
// 1000 milliseconds in a second
now.setTime(now.getTime() + 365 * 24 * 60 * 60 * 1000);
var username = getCookie("username");
// if the cookie was not found, ask for the name
if (!username) {
  username = prompt("Please enter your name:", "");
// set the new cookie
setCookie("username", username, now);
if (username) {
  document.write("Welcome to this page, " + username + ".");
  setCookie("username", username, now);
} else
  document.write("You refused to enter your name.");
// -->

Note that this script can be placed anywhere on the page. It welcomes the user by printing some text where you placed the script.

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