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Introduction to Real Time Search

The Real Time Search this article relates to is a dll that comes included in the Web Client Software Factory one of Microsoft's patterns and practices downloads. What it can do and what this example will demonstrate is adding the ability cause a post back that will refresh an update panel as the users types into a search box. This can give a great effect and make a web app really user friendly in scenarios like searching photo's, emails or any general list.

First late me state though that this is in no way the most optimal way program. In most scenarios you could built a better result using something like JSON as their will be a lot less data transfer, which is also a general reason to avoid update panels. However this is also very quick and very easy to implement, not to mention if you've ever used update panels before you already know 90% of what's needed. This can also only work in situations where you have a good search that is going to return the result quickly, rather than leaving the user sitting there trying to work out why nothing's happening and where the search button has gone.

Implementing Real Time Search

For this example I will be filtering a table from a DB based on the search criteria and refreshing a Grid View with the results. I will be using a normal C# Web Site project with the Adventure Works sample DB from Microsoft. DB connection will be done using LINQ to EntityFramework, however there is no need to use this it is just my preference for the example.

First off set up you're website and db and make sure both are working with no problems. As results will be displayed in an Update Panel, get one of these along with a script manager added to your page, so it looks something like this:

1<form id="form1" runat="server">
2<div>
3<asp:ScriptManager ID="ScriptManager1" runat="server">
4</asp:ScriptManager>
5<asp:UpdatePanel ID="UpdatePanel1" runat="server">
6<ContentTemplate></ContentTemplate>
7</asp:UpdatePanel>
8</div>
9</form>

Next let's get the search working in the normal method, so I'm going to create my Entity Model and add a textbox and gridview to show the results. Again you can connect and show your results however you want. You should now have something like this in your aspx file:

1<form id="form1" runat="server">
2<div>
3<asp:ScriptManager ID="ScriptManager1" runat="server">
4</asp:ScriptManager>
5

6<asp:TextBox ID="txtSearch" runat="server" OnTextChanged="TextChanged" Text=""></asp:TextBox>
7

8<asp:UpdatePanel ID="UpdatePanel1" runat="server">
9<ContentTemplate>
10

11<asp:LinqDataSource ID="LinqDataSource1" runat="server" onselecting="LinqDataSource1_Selecting">
12</asp:LinqDataSource>
13

14<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataSourceID="LinqDataSource1">
15<Columns>
16<asp:BoundField DataField="ProductID" HeaderText="ProductID"
17ReadOnly="True" SortExpression="ProductID" />
18<asp:BoundField DataField="Name" HeaderText="Name"
19ReadOnly="True" SortExpression="Name" />
20<asp:BoundField DataField="ProductNumber" HeaderText="ProductNumber" ReadOnly="True" SortExpression="ProductNumber" />
21<asp:BoundField DataField="Color" HeaderText="Color"
22ReadOnly="True" SortExpression="Color" />
23<asp:BoundField DataField="SafetyStockLevel" HeaderText="SafetyStockLevel"
24ReadOnly="True" SortExpression="SafetyStockLevel" />
25<asp:BoundField DataField="ReorderPoint" HeaderText="ReorderPoint"
26ReadOnly="True" SortExpression="ReorderPoint" />
27</Columns>
28</asp:GridView>
29</ContentTemplate>
30

31</asp:UpdatePanel>
32</div>
33</form>

And this in your code behind:

1protected void LinqDataSource1_Selecting(object sender, LinqDataSourceSelectEventArgs e)
2{
3Model.AdventureWorks2008Entities AdventureWorkds = new Model.AdventureWorks2008Entities();
4var products = from p in AdventureWorkds.Product
5where p.Name.Contains(txtSearch.Text)
6select p;
7e.Result = products;
8}

Next its time to add the Real Time Search. Make sure you have the dll downloaded (you may need to compile the download to get it) and add it to your bin folder. Add the following to your page in the relevant places:

1<%@ Register Assembly="RealTimeSearch" Namespace="RealTimeSearch" TagPrefix="cc1" %>
2

3<cc1:RealTimeSearchMonitor ID="RealTimeSearchMonitor1" runat="server" AssociatedUpdatePanelID="UpdatePanel1">
4<ControlsToMonitor>
5<cc1:ControlMonitorParameter EventName="TextChanged" TargetID="txtSearch" />
6</ControlsToMonitor>
7</cc1:RealTimeSearchMonitor>

Important things to notice here are the AssociatedUpdatePanelId which tells the control what it has to refresh and the controls to monitor section which sets what the control to watch is called and the event name that will be fired when the post back is created. You will now need to corresponding control in your code behind like so:

1protected void TextChanged(object sender, EventArgs e)
2{
3GridView1.DataBind();
4}

Run the site and  you should find that the grid view now updates as you type (all be it with a slight delay).

To improve you can add other controls like update progress to show something happening which will help with any delays in displaying the results.

Visual Studio 2010 – Snippet Support

This week I have been playing around with the Beta 1 of Visual Studio 2010 and one thing I have to say I like is the new Snippet Support. We're all used to using it's InteliSense support allowing us to only type <aso:Bu and then hit space if we wanted to add a .NET button control to the page, but Snippets takes that a step further. Have a look at this example of adding a MultiView control to the page.

Adding A MultiView Control

The normal method would be to type <asp:Multi and then hit space to complete the word, followed by adding an ID, runat etc. All of which would be made easier with the current InteliSense support. Now though you can just type <mu and the Multiview snippet will be highlighted.

Hit tab and the word will be completed as below.

Hit tab again though and all the other stuff you were about to type is entered for you.

An auto ID is given, the runat and activeviewindex properties are also written for you along with the first view automatically added.

Snippet support isn't just limited to .NET controls either, it will also work with HTML markup and JavaScript.

HTML Example

In this HTML example of an "A" tag you can see as simple as an "A" tag may be, snippets can save you time even here by automatically writing the whole thing, and then recognising that you will want to change the values of the two sections and thus makes that even easier by then letting you tab between the two sections.

So there you have it, we can now all wonder how we ever survived having to write the first couple of letters of each word, when really all we ever needed to do was write the first couple of letters of the main tag and have the rest written for us.

How to search inside Stored Procedures?

A common problem faced by many developers when it comes to databases and SQL Server is how to search the text inside a stored procedure.

In many systems particularly older Classic ASP solutions, functional code has been moved from the actual application to stored procedures inside the database. This is usually because it will either run faster here, or because it was just a lot easier to perform the necessary task using TSQL. Following this though comes the problem of how you can search what's in all those stored procedures, especially when you're getting into the hundreds of them. Let's say there was a Users table that contained fields for an address, but that now needs to be moved to a table of its own, you would need to search all the code for things accessing those table columns but SQL Server Management Studio certainly doesn't provide any search box's with the power to do this.

Never fear though syscomments is here. Syscomments contains the original text from amongst other things all the Stored Procedures in the DB s all you need to do is search that for what you're looking for:

1Select OBJECT_NAME(id), [text]
2From syscomments
3Where [text] like '%Create%'

The function OBJECT_NAME will also help you by converting the id number in the result set into the actual name of the stored procedure (or view, function etc). If you wanted to limit the result to just stored procedures you can add the following line to the where clause:

1AND OBJECTPROPERTY(id, 'IsProcedure') = 1

Refreshing an UpdatePanel using JavaScript

Update panels provide a really easy way to add partial page refresh's to a web page in order to give a more user friendly experience that's more like a common desktop App. By default a button within that update panel will cause a post back and so long as no elements outside of the update panel are affected in the post back only it will refresh. However what do you do if you need to refresh a panel based on something outside of the update panel. One option is just to place a hidden button within the Update Panel and trigger that to post back, however this appears a little hacky. The solution is to use JavaScript and the _doPostBack method.

The following bit of code is all you really need:

1<script type="text/javascript">
2function refreshUpdatePannel(param) {
3var prm = Sys.WebForms.PageRequestManager.getInstance();
4prm._doPostBack('<%=UpdatePanel1.ClientID %>', param);
5prm.add_endRequest(refreshUpdatePanelComplete);
6}
7

8

9function refreshUpdatePanelComplete() {
10//add code here for when the update pannel is refreshed
11}
12</script>

All you need to add is something to call the function.

The second parameter is optional and provides a way of passing some information back to the server to let it know what has just happened on the page.

When the update panel has finished refreshing the refreshUpdatePanelComplete function will fire so more JavaScript can be added if needed e.g. To reset whatever just happened on the page that caused the initial postback.