How to traverse checkbox in Asp.net

During development, we often need to determine the number of checkboxes selected and make a summary.
First, the most common is to directly traverse the checkbox that exists in the page. The basic idea is to traverse all the controls in the page and then determine whether the control type is system. web. UI. webcontrols. the checkbox is fine. The Code is as follows:

Foreach (control CT in form1.controls)
{
If (Ct. GetType (). tostring (). Equals ("system. Web. UI. webcontrols. checkbox "))
{

Checkbox cb = (checkbox) CT;
CB. Checked = true;

}
}

The second is that we often use the gridview control to display data. We often add a column of checkbox to control selection and select all. How can we traverse the checkbox in the gridview? I made a simple example here

You can see that after you click Select All, all the checkboxes in the gridview are selected as follows.

Protected void checkbox#checkedchanged (Object sender, eventargs E)
{
Int I;
If (checkbox) sender). Checked)
{
For (I = 0; I <gridview1.rows. Count; I ++)
{
(Checkbox) gridview1.rows [I]. findcontrol ("checkbox2"). Checked = true;
}
}
Else
{
For (I = 0; I <gridview1.rows. Count; I ++)
{
(Checkbox) gridview1.rows [I]. findcontrol ("checkbox2"). Checked = false;
}
}
}
First, add the checkbox‑checkedchanged event to the checkbox1, that is, the all-selected checkbox. Note that many of your friends did this but did not succeed, because the atuopostback of checkbox must be set to true, otherwise, the status will not change.