Our aim is to randomly display a text string from a set. It involves the following steps
- Initializing an array
- Storing the text strings in that array
- Finding the length of this array
- Using the Math.random() to generate a random number
- Using the randomly generated number as index for retrieving a text string from the array.
- Displaying the text through an alert() box or document.write()
var text_st = new Array("String1", "String2", "String3", "String4", "String5", "String6", "String7", "String8", "String9", "String10"); var l = text_st.length; var rnd_no = Math.floor(l*Math.random()); alert(text_st[rnd_no]);
Note: Array are zero-indexed, thus, we can use the value of variable l (length of the array) directly because we are using floor() to round down to an integer.
When to randomly display text on a web page?
I have used this code on several web sites to display a random testimonial from a set. So each time the web page loads a testimonial is selected and displayed at random. The code can also be used to display a random quote or a greeting.