Selecting multiple checkboxes in a DataGrid control

Introduction

In this article, I will explain how to select multiple checkboxes which are inside a DataGrid web server control.

foreach(DataGridItem dgi in myGrid.Items) 
{ 
    CheckBox myCheckBox = (CheckBox)dgi.Cells[0].Controls[1];
    if(myCheckBox.Checked == true)
    {
        name+= myGrid.DataKeys[dgi.ItemIndex].ToString();
        name+=",";
    }
}

Explanation

In the code, myGrid refers to a DataGrid. All the code provided is placed inside the ItemCommand Event of the DataGrid control. First, we iterate through the DataGrid items using the foreach loop.

foreach(DataGridItem dgi in myGrid.Items)

In the body of the foreach loop, we assign our newly created instance of CheckBox the value of the checkbox presented in the DataGrid control. Which in this case lies in the first column of the DataGrid.

CheckBox myCheckBox = (CheckBox)dgi.Cells[0].Controls[1];

After that, we check that if the checkbox has been checked or not, using a simple if statement.

if(myCheckBox.Checked == true)

Once we find out that the checkbox has been checked, we use the DataKeys property of the DataGrid control to get the appropriate value from the checked row. In this case, I have set the DataKeys property to name, getting name value in my string name variable.

name+= myGrid.DataKeys[dgi.ItemIndex].ToString();

You should always assign some primary key value to the DataKeys collection so that you can always retrieve more data with that value.