Member Avatar for kool.net

hi,
pls. tell me how to select value from a check box, & from a list box or combo box.
actually i m new to c# , so sorry for this stupid question but i need your help.
Thanx in advance.
Happy Diwali
Regards
~ Dimple

  • 6 Contributors
  • 6 Replies
  • 241 Views
  • 4 Days Discussion Span
  • Latest Post Latest Post by avirag

Dani AI

Generated

Builds on the pointers from , and with practical patterns that work smoothly in real WinForms apps: typed binding for list/combos, using the control Tag to carry an ID for checkboxes, and a safe way to send selected GridView rows to the database.

Bind a list of typed objects so the UI shows friendly text while code uses the ID:

class Option { public int Id; public string Label; }
comboBox.DataSource = optionsList;
comboBox.DisplayMember = "Label";
comboBox.ValueMember = "Id";

// safely read the chosen object
var chosen = comboBox.SelectedItem as Option;
if (chosen != null) {
    int id = chosen.Id;
    string text = chosen.Label;
}

For multiple choice rendered as checkboxes, attach the underlying value to the control so event handlers can update the model without parsing text:

var cb = new CheckBox { Text = item.Label, Tag = item.Id };
cb.CheckedChanged += (s,e) => {
    var id = (int)((CheckBox)s).Tag;
    var on = ((CheckBox)s).Checked;
    // update backing data (list/db) for id => on
};
panel.Controls.Add(cb);

To collect checked rows from a DataGridView and update the DB, gather IDs first and send them as a structured parameter (avoids string concatenation and SQL injection):

var ids = new List<int>();
foreach (DataGridViewRow r in dgv.Rows)
    if (Convert.ToBoolean(r.Cells["Select"].Value))
        ids.Add(Convert.ToInt32(r.Cells["Id"].Value));

var dt = new DataTable();
dt.Columns.Add("Id", typeof(int));
foreach (var i in ids) dt.Rows.Add(i);
// pass dt as a SqlParameter with SqlDbType.Structured to a stored proc that accepts a TVP

Troubleshooting: always null-check selections, keep UI logic separate from data access, and prefer parameterized/structured DB calls for bulk updates. These patterns scale better than reading control text or building inline SQL.

Recommended Answers

All 6 Replies

Member Avatar for kvprajapati

For checkBox, use Checked and CheckState property.
List and ComboBox; use SelectedValue property.

commented: good suggestion +5
Member Avatar for sanch01r

The example below will retrieve the value of a checkbox and display it in a messagebox on a button click event.

if (checkBox1.Checked)
            {
                MessageBox.Show(checkBox1.Text.ToString());
            }
Member Avatar for DdoubleD

It wasn't clear to me whether your question was for obtaining the state, as you have already been directed, or you are wanting to set the state, which I will throw out some additional direction below.

// ListBox method to select an item...
public void SetSelected(int index, bool value);
public ListBox.SelectedObjectCollection SelectedItems { get; } // to see all items selected...
// and, to capture when the selection is changing:
public event EventHandler SelectedIndexChanged;

// RadioButton method to get/set state:
public bool Checked { get; set; }
// and, to capture when the state has been changed:
public event EventHandler CheckedChanged;

// ComboBox methods to select item:
public override int SelectedIndex { get; set; }
public object SelectedItem { get; set; }
// and, to capture when the selection has changed:
public event EventHandler SelectedIndexChanged;

If you search on these, you should be able to find all the example code you need to see/understand how these are implemented in a form.

Cheers!

Edited by DdoubleD because: n/a
Member Avatar for kool.net

Hey
Thanks to all.

Member Avatar for miracle007

how to gridview selected checkbox row send (pass) to same sqldatabase

Member Avatar for avirag

Please mark this thread as solved, if your problem is solved.......
Thank you..

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.