Develop Reference

Conditional Image Template Column

I am using Visual Studio 2015 and entity framework 6. I have a GridView and I want the status column on it to show four different types of images, depending on string in that field from the database. I want it to be done with a template.
Here is my GridView:
<asp:GridView ID="gvStatus" runat="server" Height="184px"
Width="1359px" AutoGenerateColumns="false" AllowSorting="true" >
<HeaderStyle Font-Bold="true" Font-Size="16pt" BackColor="#cc0000" ForeColor="Black"/>
<RowStyle Font-Size="12pt" BackColor="#afadad" ForeColor="White"/>
<AlternatingRowStyle BackColor="#afadad" ForeColor="White" />
<Columns>
<asp:CommandField HeaderText="" SelectText="Delete" ShowSelectButton="true" ControlStyle-ForeColor="White" />
<asp:BoundField HeaderText="Status" DataField="Status" />
</Columns>
</asp:GridView>
How do I get the status column to show up with four different images, dependent on what string is there?

You could do it like this:
<Columns>
<asp:TemplateField >
<HeaderStyle Width="10%" />
<ItemTemplate>
<asp:Image ID="Image1" runat="server" ImageUrl='<%#GetImagePath(Eval("img").ToString())%>' />
</ItemTemplate>
</asp:TemplateField>
</Columns>
And in the code behind:
public string GetImagePath(object value)
{
if (string.IsNullOrEmpty(Convert.ToString(value))) return string.Empty;
var x = int.Parse(value.ToString());
return x > 0 ? "Your Image Path" : "Default Image Path";
//Here I show two different types of images depending on int value in that field from the database you can change it to four type with if-else and also depending on string value
}

Selection of checkboxes lost during pagination of gridview

I have a problem in gridview, as per requirement i have set No of Records per page = 4 in gridview. I have to select Checkbox against every complaint but problem is then when i got to next pge in gridview and e.g fro 1 to 2 then when i come back to page 1 then it doesn't show TICK in check boxes . It doesn't remember my selection when i browse to and back to page.
<asp:GridView ID="GridViewSmsComplaints" AllowPaging="True" PageSize="4" runat="server" AutoGenerateColumns="False" CssClass="mGrid" BorderColor="#333333" Width="550px" OnPageIndexChanging="GridViewSmsComplaints_PageIndexChanging" >
<Columns>
<asp:BoundField HeaderText="ID" DataField="ID" />
<asp:BoundField HeaderText="Recieving Date" DataField="RecievingDate" />
<%--<asp:BoundField HeaderText="ToMobileNo" DataField="ToMobileNo" /> --%>
<asp:BoundField HeaderText="FromMobileNo" DataField="FromMobileNo" />
<asp:BoundField HeaderText="Message" DataField="Message" >
<ItemStyle Wrap="True" />
</asp:BoundField>
<asp:TemplateField HeaderText="IsComplaint">
<ItemTemplate>
<asp:CheckBox ID="ckboxIsComplaint" runat="server" Checked='<%# Convert.ToBoolean(Eval("IsComplaint").ToString()) %>' />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>

please check the above link.here your problem was clearly explained here.i think so it may be helpfull

As per comments...
If you do not update the underlying database by processing the OnCheckChanged event of the check box, then it will simply be reading the same data all the time.
From How to add event for Checkbox click in Asp.net Gridview Column, I have extracted the required information and tried to modify to fit your initial question.
<asp:TemplateField HeaderText="IsComplaint">
<ItemTemplate>
<asp:CheckBox ID="ckboxIsComplaint" runat="server" Checked='<%# Convert.ToBoolean(Eval("IsComplaint").ToString()) %>' OnCheckedChanged="chk_CheckedChanged" AutoPostBack="true/>
</ItemTemplate>
</asp:TemplateField>
add checkbox change event in aspx.cs page
protected void chk_CheckedChanged(object sender, EventArgs e)
{
GridViewRow row = ((GridViewRow)((CheckBox)sender).NamingContainer);
<your data source>.Rows[row.DataItemIndex]["B"] = ((CheckBox)GridViewSmsComplaints.Rows[row.RowIndex].FindControl("ckboxIsComplaint")).Checked;
}

GridView - Set focus to specific cell

I've seen lots of posts out there for this question, however, they all suggest we use methods like: dgv.CurrentCell or dgv.Rows[row].Cells[cellno].Selected. Intellisense finds no such methods. I have a textbox in a gridview, where I use the OnTextChanged method. Then, in my C# code, I update this quantity, then the grid refreshes automatically, and goes back to the top row, even though we've scrolled down a couple of pages. I've also tried putting in the MaintainScrollPositionOnPostback="true" in the 'Page' section of my .aspx page and that didn't seem to do anything. We're on .Net Framework 4.0.
<asp:GridView ID="gvOrderDetails" runat="server" AlternatingRowStyle-BackColor="#FAFAFA" Width="940px" AutoGenerateColumns="False" AllowSorting="True" OnSorting="SortOrderDetails"
OnRowCommand="gvOrderDetails_RowCommand" EmptyDataText="No Data to Display"
DataKeyNames="STOREORDNUM" HeaderStyle-Height="22px"
onselectedindexchanged="gvOrderDetails_SelectedIndexChanged">
<AlternatingRowStyle BackColor="White" /><EditRowStyle BackColor="#2461BF"/>
<FooterStyle BackColor="LightGray" Font-Bold="False" ForeColor="Black" />
<HeaderStyle BackColor="LightGray" Font-Bold="False" ForeColor="Black" BorderWidth="1px" BorderColor="Gray"/><PagerStyle BackColor="#2461BF" ForeColor="White" HorizontalAlign="Center" />
<RowStyle BackColor="#EFF3FB" Height="22px"/>
<Columns>
<asp:BoundField DataField="ITMCD" HeaderText="Item Code" SortExpression="ItemCode" >
</asp:BoundField>
....
<asp:TemplateField HeaderText="Order Qty" SortExpression="OrderQty" >
<ItemTemplate>
<asp:TextBox ID="OrderQty" runat="server" Width="36" MaxLength="5" class="numberinput" AutoPostBack="true" OnTextChanged="buttonUpdateQty_Click" Text='<%# Bind("ORDERQTY") %>' ></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
In the code behind, I've tried these two things:
gvOrderDetails.Rows[row.RowIndex].FindControl("OrderQty").Focus();
gvOrderDetails.Rows[row.RowIndex].Cells[7].Controls[0].Focus();

You need to cast the required cotrol cell into Textbox control and then call the Focus() method on it.
Try This:
TextBox txtOrderQty = (TextBox) gvOrderDetails.Rows[row.RowIndex].FindControl("OrderQty");
txtOrderQty.Focus();

Add a handler to SelectedindexChange Event of your grid view
Gridview1.SelectedRow.Focus();

Add sorting to a Nested Gridview ASP.net with C#

I have searched high and low for how to implement this on my page. I have a top level gridview which allows sorting and nested gridviews which are dynamically generated when the page compiles so 'x' number of nested gridviews which are inside dynamic html divs which can be toggled from invisible to visible at the users command. The problem I have is that I cannot figure out how to allow sorting on these nested gridviews without collapsing the divs/causing a postback.
Below shows how the master gridview (gvSalesDiv) and the nested gridview (gvTheDivisionCustomers) are generated in asp.net
<asp:GridView ID="gvSalesDiv" AllowSorting="true" onsorting="GridView1_Sorting" runat="server" GridLines="Both" OnRowDataBound="gvOrderLineDetail_RowDataBound" AutoGenerateColumns="False"
Width="100%" Height="210px" BackColor="WhiteSmoke" AlternatingRowStyle-BackColor="#DADDE2"
HeaderStyle-Font-Size="Medium" Visible="true">
<Columns>
<asp:TemplateField HeaderText="Toggle Detail">
<ItemTemplate>
<a href="javascript:switchViews('div<%# Eval("SalesDivision") %>');">
<img id="imgdiv<%# Eval("SalesDivision") %>" alt="toggle" border="0"
src="/salesconsole/toggle-off.png" />
</a>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="SalesDivision" HeaderText="Sales Division">
<ItemStyle Font-Bold="True" ForeColor="CornflowerBlue" HorizontalAlign="Center"></ItemStyle>
</asp:BoundField>
<asp:BoundField DataField="LastDay" SortExpression="LastDay" DataFormatString="{0:C}" HeaderText="Last 24 Hours" >
</asp:BoundField>
<asp:BoundField DataField="LastWeek" SortExpression="LastWeek" DataFormatString="{0:C}" HeaderText="Last 7 Days" >
</asp:BoundField>
<asp:BoundField DataField="Last30Days" SortExpression="Last30Days" DataFormatString="{0:C}" HeaderText="Last 30 Days" >
</asp:BoundField>
<asp:BoundField DataField="Last3Months" SortExpression="Last3Months" DataFormatString="{0:C}" HeaderText="Last 3 Months" >
</asp:BoundField>
<asp:BoundField DataField="Last6Months" SortExpression="Last3Months" DataFormatString="{0:C}" HeaderText="Last 6 Months" >
</asp:BoundField>
<asp:BoundField DataField="LastYear" SortExpression="LastYear" DataFormatString="{0:C}" HeaderText="Last Year" >
</asp:BoundField>
<asp:TemplateField>
<ItemTemplate>
<tr>
<td colspan="100">
<div id="div<%# Eval("SalesDivision") %>" style="display:none;position:relative;left:25px;" >
<h3 title="<%# Eval("SalesDivision") %> Sales"><%# Eval("SalesDivision") %> Sales Breakdown</h3>
<asp:GridView ID="gvTheDivisionCustomers" AllowSorting="true" onsorting="GridView2_Sorting" BackColor="WhiteSmoke" AlternatingRowStyle-BackColor="#DADDE2"
Width="100%"
AutoGenerateColumns="false" runat="server">
<Columns>
<asp:TemplateField HeaderText="Show More Detail">
<ItemTemplate>
<a href="sales-customers-detail.aspx?CustomerID=<%# Eval("CustomerID") %>&CustomerName=<%# Eval("CustomerName") %>" target="_blank" style="color:Blue; text-decoration:underline"> More Details
</a>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="CustomerID" HeaderText="ID"/>
<asp:BoundField DataField="CustomerName" HeaderText="Name" />
<asp:BoundField DataField="Last24Hours" HeaderText="Last 24 Hours" SortExpression="LastDay" DataFormatString="{0:C}" />
<asp:BoundField DataField="Last7Days" HeaderText="Last 7 Days" SortExpression="Last7Days" DataFormatString="{0:C}" />
<asp:BoundField DataField="Last30Days" HeaderText="Last 30 Days" SortExpression="Last30Days" DataFormatString="{0:C}" />
<asp:BoundField DataField="Last3Months" HeaderText="Last 3 Months" SortExpression="Last3Months" DataFormatString="{0:C}" />
<asp:BoundField DataField="Last6Months" HeaderText="Last 6 Months" SortExpression="Last6Months" DataFormatString="{0:C}" />
<asp:BoundField DataField="LastYear" SortExpression="LastYear" HeaderText="Last Year" DataFormatString="{0:C}" />
</Columns>
</asp:GridView>
</div>
</td></tr>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
I populate the master gridview on Page_Load and the nested gridviews are created using the OnRowDataBound method. I have a sorting method for the master gridview which works fine as well. Below is the OnSorting method for the nested gridview, which is where I am stuck...I cannot access this object
protected void GridView2_Sorting(Object sender, GridViewSortEventArgs e)
{
// TO DO : Sort the nested gridview....All I can get at is the sort expressions or
cast the sender into a gridview but even then I wouldn't know the correct SQL query to bind with unless I knew which 'div' I was in...
}

So basically we can say, that you are looking for an ID or something wherewith you can create the query for the sorting method?
If that is correct we can find a solution.
Put a new label inside the first gridviews(gvSalesDiv) ItemTemplate like this one:
<asp:Label ID="lblID" runat="server" Text='<%# Bind("Id") %>'></asp:Label>
And in the codebehinde you can find it in this was:
Label lblID = (Label)((GridView)sender).NamingContainer.FindControl("lblID");
Hope it works!

If you are looking for how to get the parent div the gridview resides in, you can use this:
First, you need to cast the sender to a gridview, then create an html element and cast it to the gridview's parent. Like this:
Dim test As Button = CType(sender, Button)
Dim div As HtmlGenericControl
div = CType(test.Parent, HtmlGenericControl)
Dim t As String = test.ID
In this example, I'm casting the sender to a button but you can easily change this. IN this example, you will need to have the div run at the server, using " runat="server"". If you do not want to create it on the server side, you can change how you cast from a HTMLGenericControl to ContentPlaceHolder. Let me know if this helps or you need more information.

Difference between <Fields> and <Columns> in <asp:GridView>

Well it so happens that I am kind of a novice to asp.net and trying to create a Grid whose source is declared programmatically.
In the process, I came across 2 tags Fields and Columns. Can anyone please tell me how they are different?
EDIT: I went through some sample MSDN examples, and for all I can tell it seems to me they can be used interchangeably(though I have a feeling thats not true!).
Check this out:
<asp:GridView ID="GridView1" runat="server"
AutoGenerateColumns="False" DataKeyNames="EmployeeID" DataSourceID="ObjectDataSource1">
<Columns>
<asp:BoundField DataField="LastName" HeaderText="LastName"
SortExpression="LastName" />
<asp:BoundField DataField="FirstName" HeaderText="FirstName"
SortExpression="FirstName" />
<asp:BoundField DataField="Title" HeaderText="Title"
SortExpression="Title" />
<asp:BoundField DataField="HireDate" HeaderText="HireDate"
SortExpression="HireDate" />
</Columns>
</asp:GridView>
And then there is:
<asp:GridView ID="GridView1" runat="server" AllowPaging="True"
AutoGenerateRows="False" DataKeyNames="ProductID"
DataSourceID="ObjectDataSource1" EnableViewState="False">
<Fields>
<asp:BoundField DataField="ProductName" HeaderText="Product"
SortExpression="ProductName" />
<asp:BoundField DataField="CategoryName"
HeaderText="Category"
ReadOnly="True" SortExpression="CategoryName" />
<asp:BoundField DataField="SupplierName"
HeaderText="Supplier"
ReadOnly="True" SortExpression="SupplierName" />
<asp:BoundField DataField="QuantityPerUnit"
HeaderText="Qty/Unit" SortExpression="QuantityPerUnit" />
<asp:BoundField DataField="UnitPrice"
DataFormatString="{0:c}"
HeaderText="Price"
HtmlEncode="False" SortExpression="UnitPrice" />
</Fields>
</asp:GridView>
Seem similar or is it just me??!
Thanks for helping.

Columns is just the surrounding tag for the fields which are
TemplateFields with any controls you want or
BoundFields which are created automatically
So Columns enclose the list of fields in the GridView.
<Columns>
<asp:Boundfield datafield="StudentID"
readonly="true"
headertext="Student ID"/>
<asp:TemplateField HeaderText="Student" HeaderStyle-HorizontalAlign="Left">
<ItemTemplate>
<asp:label runat="server" Font-Bold="true" ID="LblStudent" Text='<%# Bind("Student") %>'></asp:label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Inner Grid">
<ItemTemplate>
<asp:GridView ID="Grid2" AutoGenerateColumns="false" runat="server" GridLines="None" Width="300">
<RowStyle CssClass="GridViewRowStyle" />
<AlternatingRowStyle CssClass="GridViewAlternatingRowStyle" />
<HeaderStyle CssClass="GridViewHeaderStyle" />
<SelectedRowStyle BackColor="Aqua" />
<Columns>
<asp:TemplateField HeaderText="Student" HeaderStyle-HorizontalAlign="Left">
<ItemTemplate>
<asp:label runat="server" Font-Bold="true" ID="LblStudent" Text='<%# Bind("Student") %>'></asp:label>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</ItemTemplate>
</asp:TemplateField>
</Columns>
As you can see, a TemplateField could also contain another nested GridView.

Am I blind or wat!
After I posted this question I went back to my drawingboard and as it turns out, there is no Fields tag in asp:GridView, right?!
Please do let me know if this is true people(and prove me silly!)

Putting aside this particular control for a moment, it might be helpful to look at this from a general computer science point of view.
In classic programming (ANY LANGUAGE), a FIELD would be the INTERSECTION of a row and a column -- a discrete piece of data. For example, if a table has 20 rows of data containing first and last names, if you went to the 19th row and looked in the "first name" column, you've got a FIELD. Perhaps it contains the discrete data "JOHN".
COLUMNS then would be collections of like data -- in this example, you have the two columns "first name" and "last name". Columns would have attributes such as a data type, maximum length, constraints (are nulls OK?, etc.) and so forth.
Some may quibble with my definitions and say that individual cells in a COLUMN would be called a FIELD. It's not uncommon to hear that. I would reply that for a table with a single column, it'd be especially true :-) But the takeaway point is this: COLUMNS are generally containers for smaller, more discrete items such as FIELDS. FIELDS typically refer to a single piece of data, such as you'd find at the intersection of a row and column in a database table.