JavaScript Examples Bible - UserWorks Technologies

uniqueID
Chapter 1 ✦ Generic HTML Element Objects (Chapter 15)
NN2 NN3 NN4 NN6 IE3/J1 IE3/J2 IE4 IE5 IE5.5
Compatibility ✓ ✓
Example
Listing 15-18 demonstrates the recommended syntax for obtaining and applying
a browser-generated identifier for an object. After you enter some text into the text
box and click the button, the addRow() function appends a row to the table. The
left column displays the identifier generated via the table row object’s uniqueID
property. IE5+ generates identifiers in the format “ms__idn”, where n is an integer
starting with zero for the current browser session. Because the addRow() function
assigns uniqueID values to the row and the cells in each row, the integer for each
row is three greater than the previous one. There is no guarantee that future generations
of the browser will follow this format, so do not rely on the format or
sequence in your scripts.
Listing 15-18: Using the uniqueID Property
Inserting an IE5+/Windows Table Row
function addRow(item1) {
if (item1) {
// assign long reference to shorter var name
var theTable = document.all.myTable
// append new row to the end of the table
var newRow = theTable.insertRow(theTable.rows.length)
// give the row its own ID
newRow.id = newRow.uniqueID
// declare cell variable
var newCell
// an inserted row has no cells, so insert the cells
newCell = newRow.insertCell(0)
// give this cell its own id
newCell.id = newCell.uniqueID
// display the row’s id as the cell text
newCell.innerText = newRow.id
newCell.bgColor = “yellow”
// reuse cell var for second cell insertion
newCell = newRow.insertCell(1)
newCell.id = newCell.uniqueID
Continued
49
elementObject.uniqueID