How to find if a Control is RadComboBox

[Zinoviy Margovskiy]

Hi,

We have a base page where we need to traverse through all controls on the current page instance and set them to ReadOnly mode.
This works fine for most of the controls but does not work for RadComboBox.  Process never gets into if (cntrl is RadComboBox) clause. Here is the function:

       private void SetControlReadOnly(Control cntrl)
        {
            if (cntrl.HasControls())
            {
                foreach (Control nestedContrl in cntrl.Controls)
                {
                    SetControlReadOnly(nestedContrl);
                }
            }
            else
            {
                if (cntrl is RadComboBox)
                {
                    RadComboBox ddl = (RadComboBox)cntrl;
                    ddl.Enabled = false;
                }
                else if (cntrl is RadInputControl)
                {
                    SetRadInputControlReadOnly((RadInputControl)cntrl);
                }
                else if (cntrl is CheckBox)
                {
                    CheckBox chk = ((CheckBox)cntrl);
                    chk.Enabled = false;
                }
                else if (cntrl is TextBox)
                {
                    TextBox txt = ((TextBox)cntrl);
                    txt.Enabled = true;
                    txt.ReadOnly = true;
                    txt.ForeColor = System.Drawing.Color.Black;
                }
            }

        }


        private void SetRadInputControlReadOnly(RadInputControl input)
        {
            input.Enabled = true;
            input.ReadOnly = true;
            //input.BorderStyle = BorderStyle.None;
            input.DisabledStyle.ForeColor = System.Drawing.Color.Black;
        }

[Kalina]

Hello Zinoviy Margovskiy,

In fact your approach is correct, just note that RadComboBox in fact "has controls" (RadComboBoxHeaderFooterControl, RadComboBoxItem etc.)

That is why the check "if (cntrl.HasControls())" leads to recursive call of SetControlReadOnly method and attempt of disabling the RadComboBox child-controls not the RadComboBox itself.

I made a small change in your code and now it works properly:

protected void Page_Load(object sender, EventArgs e)
    {
        SetControlReadOnly(Page.Form);
    }
    private void SetControlReadOnly(Control cntrl)
    {


        if (cntrl.HasControls())
        {
            if (cntrl is RadComboBox)
            {
                RadComboBox ddl = (RadComboBox)cntrl;
                ddl.Enabled = false;
            }

            foreach (Control nestedContrl in cntrl.Controls)
            {
                SetControlReadOnly(nestedContrl);
            }
        }
        else
        {
            //if (cntrl is RadComboBox)
            //{
            //    RadComboBox ddl = (RadComboBox)cntrl;
            //    ddl.Enabled = false;
            //}
            //else
            if (cntrl is RadInputControl)
            {
                SetRadInputControlReadOnly((RadInputControl)cntrl);
            }
            else if (cntrl is CheckBox)
            {
                CheckBox chk = ((CheckBox)cntrl);
                chk.Enabled = false;
            }
            else if (cntrl is TextBox)
            {
                TextBox txt = ((TextBox)cntrl);
                txt.Enabled = true;
                txt.ReadOnly = true;
                txt.ForeColor = System.Drawing.Color.Black;
            }
        }

    }


    private void SetRadInputControlReadOnly(RadInputControl input)
    {
        input.Enabled = true;
        input.ReadOnly = true;
        //input.BorderStyle = BorderStyle.None;
        input.DisabledStyle.ForeColor = System.Drawing.Color.Black;
    }

All the best,
Kalina
the Telerik team

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