使用Java脚本将下拉列表的多个选择保存到变量中

Question

I have there dropdown lists with values, and one textarea to write those valuse in. When i press button it writes values of all three selected dropdown lists, it do that every time when i press the button (it do it three times). This pice of code writes values of dropodown lists, like this: Button pressed first time: "Conntent of dropdown lists" undefinedundefined Button pressed second time: undefined"Conntent of dropdown lists"undefined Button pressed third time: undefinedundefined"Conntent of dropdown lists"

But i want values of dropdown list not "undefined"

What can you think of?

var i = 0;
function inc(){
i++;

if (i == 1){
var UkupnaPorudzbina1 = VrsteName + ' -> ' + PodvrsteName + ' -> ' + VelicineName + i;
}else if (i == 2){
var UkupnaPorudzbina2 = VrsteName + ' -> ' + PodvrsteName + ' -> ' + VelicineName + i;
}else if (i == 3){
var UkupnaPorudzbina3 = VrsteName + ' -> ' + PodvrsteName + ' -> ' + VelicineName + i;
}
var porudzba = UkupnaPorudzbina1 + UkupnaPorudzbina2 + UkupnaPorudzbina3;
    document.frmMain.PorudzbaHolder.value = porudzba ;
}

VrsteName is:

VrsteName = document.frmMain.Vrste.options[document.frmMain.Vrste.selectedIndex].text

PodvrsteName and VelicinaName are same sort

And html part is:

<textarea name="PorudzbaHolder" rows="4"> </textarea>
<input type="button" value="Dodaj porudzbinu" onClick="inc();"/>

Thx in advance...

Answer 1

This is because you are declaring only one of the three variables each time, but then referencing all three later. Try declaring your variables first and initializing them to "" :

var UkupnaPorudzbina1 = "";
var UkupnaPorudzbina2 = "";
var UkupnaPorudzbina3 = "";

Then run the rest of your code as written, but leaving the var out before each assignment to UkupnaPorudzbina .