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Selecting text

function getLengths() {

var oTextbox1 = document.getElementById(“txt1”);

var oTextbox2 = document.getElementById(“txt2”);

alert(“The length of txt1 is “ + oTextbox1.value.length + “\n”

+ “The length of txt2 is “ + oTextbox2.value.length);

}

</script>

</head>

<body>

</body>

</html>

This example uses the

length

property of the

value

to determine how many characters are in each

text box.

The

value

property can also be used to assign a new value to a text box:

<html>

<head>

<title>Changing a Textbox Value Example</title>

function setValues() {

var oTextbox1 = document.getElementById(“txt1”);

var oTextbox2 = document.getElementById(“txt2”);

oTextbox1.value = “first textbox”;

oTextbox2.value = “second textbox”;

}

</script>

</head>

<body>

</body>

</html>

In this example, clicking the button sets the first text box to

“first textbox”

and the second text box

“second textbox”

Selecting text

Both text box types support a method called

select()

, which selects all the text in the text box. In order

to work, the text box must have focus. To ensure that the text box has focus, you should always call

another method,

focus()

, before calling

select()

. (This isn’t required in all browsers, but it’s safer to

always call

focus()

first.) For example:

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