Testing Multiple Conditions with if and else

You can now create an example script using if and else. In Chapter 4, “Understanding JavaScript,” you created a simple script that displays the current date and time. This example will use conditions to display a greeting that depends on the time: “Good morning,” “Good afternoon,” “Good evening,” or “Good day.” To accomplish this, you can use a combination of several if statements:

if (hours < 10)  {
     document.write("Good morning.");
}  else if (hours >= 14 && hours <= 17)  {
     document.write("Good afternoon.");
}  else if (hours >= 17)  {
     document.write("Good evening.");
}  else {
     document.write("Good day.");
}

The first statement checks the hours variable for a value less than 10—in other words, it checks whether the current time is before 10:00 a.m. If so, it displays the greeting “Good morning.”