//?給下拉框增加項
function?insertOption(obj,?_text,?_value,?_selected){
????//?如果存在此VALUE，則編輯
????for?(var?i=0;?i<?obj.length;?i++){
????????if?(obj[i].value?==?_value){
????????????obj[i].text?=?_text;
????????????
????????????return;
????????}
????}
????
????//?若不存在此VALUE，新建????????????
????var?_option?=?document.createElement("OPTION");
????_option.text?=?_text;
????_option.value?=?_value;
????????
????obj.add(_option);
??? if (_selected) {obj.selectedIndex = obj.length-1;}

}

//?給下拉框去除某項
function?delOption(obj,_value){
????for?(var?i=0;?i<?obj.length;?i++){
????????if?(obj[i].value?==?_value){
????????????obj.remove(i);
????????????return;
????????}
????}
}
//?給多行下拉框去除某幾項(多項)
function?delMultiOption(obj,_indexArray){
????var?offset?=?0;
????for?(var?i=0;?i<?_indexArray.length;?i++){
????????obj.options.remove(_indexArray[i]+offset);
????????offset--;
????}
}
//?清除選項
function?clearOptions(obj){
??obj.options.length=0;?
}

function?getSelectedOption(obj){
????var?ret?=?new?Array();
????ret[0]?=?obj.value;
????ret[1]?=?obj.options[obj.selectedIndex].text;
????
????return?ret;????
}
//?多項下拉框的選擇項的值
function?getMultiSelectedValue(ob,excludeFirst)
{
????var?arSelected?=?new?Array();
????while?(ob.selectedIndex?!=?-1)
????{
????????if?(!(excludeFirst?&&?ob.selectedIndex?==?0)){arSelected.push(ob.value);}
????????ob.options[ob.selectedIndex].selected?=?false;
????}
????return?arSelected;
}
//?多項下拉框的選擇項的INDEX
//?ob:?控件
//?excludeFirst:?是否排除第一項(第一項有時為說明項)
function?getMultiSelectedIndex(ob,excludeFirst)
{
????var?arSelected?=?new?Array();
????while?(ob.selectedIndex?!=?-1)
????{
????????if?(!(excludeFirst?&&?ob.selectedIndex?==?0)){arSelected.push(ob.selectedIndex);}
????????ob.options[ob.selectedIndex].selected?=?false;
????}
????return?arSelected;
}

本系統，待補充及完善，長期未完成稿，歡迎指正 ：)

轉載于:https://www.cnblogs.com/syveen/archive/2007/09/04/881617.html

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