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

Answer 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;
    }

Answer 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"];
}

Answer 3

Use LINQ:

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

Answer 4

The ToString() is not going to give you what you want: You need somthing more like

private string getRadioValue(ControlCollection clts, string groupName)
{
    var ret = "";
    foreach (Control ctl in clts)
    {
        if (ctl.Controls.Count != 0)
        {
            ret = getRadioValue(ctl.Controls, groupName);
        }
        if (!string.IsNullOrEmpty(ret)) {
          return ret;
        }
        var rb = ctl as RadioButton;
        if (rb != null && rb.GroupName == groupName && rb.Checked)
                return = rb.Attributes["Value"];
        }
    }
    return ret;
}