Javascript：使用动态ID获取文本框值

Question

I read most of the questions here but I could not find the answer to this one so I'll give it a shot!

What I'm trying to accomplsih is that when a certain radio is choosen, I want to fetch a certain textbox value. That's why I need the dynamic ID to know from which textbox I want to pick the value.

As you can see below I group my radiobuttons in groups of three.

The problem is that I can't seem to get the value out of the textbox...! No matter what I try it always returns 0(zero)

This is my html!

   <asp:RadioButton id="RadioButton1" name="directory" GroupName="sverigemot" value="50" runat="server" Text="Fri tillgång" onclick="calculatePrice()"  />
    <asp:RadioButton id="RadioButton2" name="directory" GroupName="sverigemot" runat="server" 
        Text="En artikel om dagen(30/mån)" value="25" onclick="calculatePrice()" />
    <asp:RadioButton id="sverigemot1" name="choice" GroupName="sverigemot" runat="server" value="0"
        Text="Skriv antalet artiklar" onclick="calculatePrice()" />
    <asp:TextBox ID="textbox1" name="sverigemot1" runat="server" Width="106px"></asp:TextBox>
        <br />
        <asp:RadioButton id="RadioButton4" name="directory" GroupName="handlaihop" value="50" runat="server" Text="Fri tillgång" onclick="calculatePrice()"  />
    <asp:RadioButton id="RadioButton5" name="directory" GroupName="handlaihop" runat="server" 
        Text="En artikel om dagen(30/mån)" value="25" onclick="calculatePrice()" />
    <asp:RadioButton id="handlaihop2" name="choice" GroupName="handlaihop" runat="server" value="0"
        Text="Skriv antalet artiklar" onclick="calculatePrice()" />
    <asp:TextBox ID="textbox2" name="handlaihop1" runat="server" Width="106px"></asp:TextBox>

Here my javascript!

var selectedDirectory = document.getElementsByTagName('input');
var valueOfRadio = 0;
var y = 0;

for (var i = 0; i < selectedDirectory.length; i++) 
{
    //if the radio button is checked
    if (selectedDirectory[i].checked && selectedDirectory[i].type == 'radio')
    {

        if (selectedDirectory[i].value == '0') {
            //Puts together the dynamic name
            var dynamictbname = selectedDirectory[i].name + "1";
            //Checks the name 
            alert(dynamictbname);
            //Stores the actual textbox
            var dynamictb = document.getElementById(dynamictbname);
            alert('Value in textbox is: ' + parseInt(dynamictb.value));


            if (parseInt(dynamictb.value) == null) {
                alert('Textboxen är null');
            }
            else {
                var tbvalue = parseInt(dynamictb.value);
                valueOfRadio += parseInt(document.getElementsByName(dynamictbname));
                alert('Name and Value in textbox is: ' + dynamictbname + ' = ' + tbvalue);
                valueOfRadio += parseInt(selectedDirectory[i].value);
                y++;
            }
        }
        else {

            valueOfRadio += parseInt(selectedDirectory[i].value);
             alert(valueOfRadio);

        }

    }
} 

var divobj = document.getElementById('thePrice');
divobj.innerHTML = "value" + valueOfRadio; 

Answer 1

onchange="setValue(this);"

function setValue(node){
    var txtBoxValue = document.getElementById(node.value).value;
    alert(txtBoxValue );
}​

---

$('input[name="directory"]').change(function(){
 var selector = '#' + $(this).val();
 var txtBoxValue = $(selector).val();
})

jQuery DEMO

JavaScript DEMO

Answer 2

Guys I messed up sorry!

I had forgot to change the ID in my html.

'Im using getElementsByID, and I was searching for groupname + 1, as the ID. The ID's were

textbox1, textbox2 .... textbox99... No wonder it couldn't find it...

I confused name with ID... stupid I know!!

I rid the texboxes of their name and im using the ID instead... Here's the correct html.

<asp:RadioButton id="RadioButton1" name="directory" GroupName="sverigemot" value="50" runat="server" Text="Fri tillgång" onclick="calculatePrice()"  />
    <asp:RadioButton id="RadioButton2" name="directory" GroupName="sverigemot" runat="server" 
        Text="En artikel om dagen(30/mån)" value="25" onclick="calculatePrice()" />
    <asp:RadioButton id="RadioButton3" name="choice" GroupName="sverigemot" runat="server" value="0"
        Text="Skriv antalet artiklar" onclick="calculatePrice()" />
    <asp:TextBox ID="sverigemot1" runat="server" Width="106px"></asp:TextBox>
        <br />
        <asp:RadioButton id="RadioButton4" name="directory" GroupName="handlaihop" value="50" runat="server" Text="Fri tillgång" onclick="calculatePrice()"  />
    <asp:RadioButton id="RadioButton5" name="directory" GroupName="handlaihop" runat="server" 
        Text="En artikel om dagen(30/mån)" value="25" onclick="calculatePrice()" />
    <asp:RadioButton id="RadioButton6" name="choice" GroupName="handlaihop" runat="server" value="0"
        Text="Skriv antalet artiklar" onclick="calculatePrice()" />
    <asp:TextBox ID="handlaihop1" runat="server" Width="106px"></asp:TextBox>