Using JavaScript with GridView Control CheckBox Column

In this code snippets we will discuss about to select all the checkboxes in the gridview by selecting the header checkbox. The functions we covered here is

1. Highlighting selected row

2. Check/Uncheck all records using single checkbox.

GridView Markup

<asp:GridView ID="GridView1" runat="server"  HeaderStyle-CssClass = "header"

AutoGenerateColumns = "false" Font-Names = "Arial"

OnRowDataBound = "RowDataBound"

Font-Size = "11pt" AlternatingRowStyle-BackColor = "#C2D69B" >

<Columns>

<asp:TemplateField>

    <HeaderTemplate>

      <asp:CheckBox ID="checkAll" runat="server" onclick = "checkAll(this);" />

    </HeaderTemplate>

   <ItemTemplate>

     <asp:CheckBox ID="CheckBox1" runat="server" onclick = "Check_Click(this)" />

   </ItemTemplate>

</asp:TemplateField>

<asp:BoundField ItemStyle-Width="150px" DataField="CustomerID" HeaderText="CustomerID"  />

<asp:BoundField ItemStyle-Width="150px" DataField="City"

HeaderText="City" />

<asp:BoundField ItemStyle-Width="150px" DataField="Country"

HeaderText="Country"/>

<asp:BoundField ItemStyle-Width="150px" DataField="PostalCode"  HeaderText= "PostalCode"/>

</Columns>

</asp:GridView>

Highlight Row when checkbox is checked

<script type = "text/javascript">

function Check_Click(objRef)

{

    //Get the Row based on checkbox

    var row = objRef.parentNode.parentNode;

    if(objRef.checked)

    {

        //If checked change color to Aqua

        row.style.backgroundColor = "aqua";

    }

    else

    {   

        //If not checked change back to original color

        if(row.rowIndex % 2 == 0)

        {

           //Alternating Row Color

           row.style.backgroundColor = "#C2D69B";

        }

        else

        {

           row.style.backgroundColor = "white";

        }

    }

   

    //Get the reference of GridView

    var GridView = row.parentNode;

   

    //Get all input elements in Gridview

    var inputList = GridView.getElementsByTagName("input");

   

    for (var i=0;i<inputList.length;i++)

    {

        //The First element is the Header Checkbox

        var headerCheckBox = inputList[0];

       

        //Based on all or none checkboxes

        //are checked check/uncheck Header Checkbox

        var checked = true;

        if(inputList[i].type == "checkbox" && inputList[i] != headerCheckBox)

        {

            if(!inputList[i].checked)

            {

                checked = false;

                break;

            }

        }

    }

    headerCheckBox.checked = checked;

   

}

</script>

The above function is invoked when you check / uncheck a checkbox in GridView row

First part of the function highlights the row if the checkbox is checked else it changes the row to the original color if the checkbox is unchecked.

The Second part loops through all the checkboxes to find out whether at least one checkbox is unchecked or not.

If at least one checkbox is unchecked it will uncheck the Header checkbox else it will check it

Check all checkboxes functionality

<script type = "text/javascript">

function checkAll(objRef)

{

    var GridView = objRef.parentNode.parentNode.parentNode;

    var inputList = GridView.getElementsByTagName("input");

    for (var i=0;i<inputList.length;i++)

    {

        //Get the Cell To find out ColumnIndex

        var row = inputList[i].parentNode.parentNode;

        if(inputList[i].type == "checkbox"  && objRef != inputList[i])

        {

            if (objRef.checked)

            {

                //If the header checkbox is checked

                //check all checkboxes

                //and highlight all rows

                row.style.backgroundColor = "aqua";

                inputList[i].checked=true;

            }

            else

            {

                //If the header checkbox is checked

                //uncheck all checkboxes

                //and change rowcolor back to original

                if(row.rowIndex % 2 == 0)

                {

                   //Alternating Row Color

                   row.style.backgroundColor = "#C2D69B";

                }

                else

                {

                   row.style.backgroundColor = "white";

                }

                inputList[i].checked=false;

            }

        }

    }

}

</script>

The above function is executed when you click the Header check all checkbox When the Header checkbox is checked it highlights all the rows and checks the checkboxes in all rows.

And when unchecked it restores back the original color of the row and unchecks the checkboxes.

Note:

The check all checkboxes checks all the checkboxes only for the current page of the GridView and not all.