How To Find Checked Radio Button Using Group name My code Attached?

Question

i am trying to find the value of checked radio using group name i have method that return it but what should i pass in that method along with group name

method is here,

private string getRadioValue(ControlCollection clts, string groupName)
{
    string ret = "";
    foreach (Control ctl in clts)
    {
        if (ctl.Controls.Count != 0)
        {
            if (ret == "")
                ret = getRadioValue(ctl.Controls, groupName);
        }

        if (ctl.ToString() == "System.Web.UI.WebControls.RadioButton")
        {
            RadioButton rb = (RadioButton)ctl;
            if (rb.GroupName == groupName && rb.Checked == true)
                ret = rb.Attributes["Value"];
        }
    }
    return ret;
}

i use it like

Oc.aProjectSubmited = getRadioValue(RadioButton,"Aps");

where Aps is radio group but getting error "invalid argument" on radio button i pass ??

hopes for your suggestion thanks in advance

Solution 1

This is because you are passing RadioButton. Your method accepts ControlCollection, not a Control.

Why not pass this.Controls to pass the whole ControlCollection of the page? Or any other ControlCollection that you might be using to keep that RadioButton you want to check?

Here's an example:

    protected void Page_Load(object sender, EventArgs e)
    {
        getRadioValue(this.Controls, "Hello");
    }

    private string getRadioValue(ControlCollection clts, string groupName)
    {
        string ret = "";
        foreach (Control ctl in clts)
        {
            if (ctl.Controls.Count != 0)
            {
                if (ret == "")
                    ret = getRadioValue(ctl.Controls, groupName);
            }

            if (ctl.ToString() == "System.Web.UI.WebControls.RadioButton")
            {
                RadioButton rb = (RadioButton)ctl;
                if (rb.GroupName == groupName && rb.Checked == true)
                    ret = rb.Attributes["Value"];
            }
        }
        return ret;
    }

Solution 2

Here's a shorter version using Linq to avoid the loops...

public static string GetRadioValue(ControlCollection controls, string groupName)
{
   var selectedRadioButton = controls.OfType<RadioButton>().FirstOrDefault(rb => rb.GroupName == groupName && rb.Checked);
   return selectedRadioButton == null ? string.Empty : selectedRadioButton.Attributes["Value"];
}

Solution 3

Use LINQ:

container.Controls.OfType<RadioButton>().FirstOrDefault(r => r.GroupName == "GroupName" && r.Checked).Text;

Comments

[aiapatag]

well, ToString() will still work although it's not a best practice. I don't think this is the answer though.

[tester Joe]

@Bob what should i pass for "ControlCollection clts" ?

[Bob Vale]

@aiapatag OK didn't check that RadioButton.ToString() outputted the class name, however if an inherited control was used that used a different implementation of ToString then my answer would still work

[aiapatag]

@BobVale yes indeed. But what I'm saying is... that is not the answer to the poster's question.

[Bob Vale]

@testerJoe Guessing the value attribute for the found radio button is null or unset.

[tester Joe]

if i wanna get id of radio then i would replace ["Value"] by ["Id"] ?

[Bob Vale]

@testerJoe either rb.ID if you want the server side id or rb.ClientID if you want the client side id

[tester Joe]

@BOb i did the same Thanks

[wloescher]

Just found a similar answer from SLaks on a similar question... stackoverflow.com/questions/1797907/…

[track0]

The "similar answer" mentioned above relates to WinForms - this is a WebForms question.