Option List in HTML

Code in HTML:

‹form id="oForm" name="oForm" action="" method="POST"›
‹select id="sList" name="sList" onchange="picking(this.form.cateList)"›
‹/select›
‹/form›

Script in JavaScript:

; var position
; var len

; window.onload = function()
{ ; len = selfCate.length
; for (var i=0; i ; createOption('cateForm', 'cateList', len, 'At the end')
; document.cateForm.cateList[len].selected = true
; position = len
}

; function picking(dropDown)
{ ; var myIndex = dropDown.selectedIndex
; position = dropDown.options[myIndex].value
}

; function createOption(formName, selectName, indexValue, newText)
{ ; var objSelect = document.forms[formName].elements[selectName]
; var objOption = document.createElement("option")
; objOption.value = indexValue
; objOption.text = newText
; if(document.all && !(window.opera)) objSelect.add(objOption)
else objSelect.add(objOption, null)
}

; function removeOptions(selectId, firstNumToKeep, lastNumTokeep)
{ ; var elSel = document.getElementById(selectId)
; var total = elSel.length - lastNumTokeep - 1
; for (var i=total; i>=firstNumToKeep; i--) elSel.remove(i)
}

Special Notes:

1. In window.onload, “document.cateForm.cateList[len].selected = true” is to show what item is preselected in HTML. It is “position = len” to tell PHP what was preselected, if preselected has not been changed.

2. In picking(), apart of the need of global variable, the writing of var position = dropDown.options[myIndex].value is not recommended because some browser request variable declaration and assignment being separated.