Re: Drop Down Listnot updating when item deleted from GridView - ASP.NET Discussion Boards

Try using Failed Request Tracing[^] to diagnose the error. There's also a post on the MSDN blogs[^] which might help.

"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer

Go to IIS Set Anonymous authentication disable and windows authentication enable this will solve your problem.

Hello Mr.Shukla,

I had already done that.
It returns Error:401 and doesn't let me do anything. Frown | :(

Thanks,
Raesa

You technically should not be able to get that information, if you do, then it's coming from the server that request was made on, and not the client machine.

Below is the correct response to the query, because it came off the web server.

raesark wrote:
But it returns :
NT AUTHORITY\IUSR

If the query was made in a windows app running managed code on a client computer or server, then you would get the domain name and identity your looking for.

[edit]

You got the identity that made the request, which is anonymous or IIS_USR in IIS5 and IIS6

by design, Microsoft is closing the loopholes in asp.net when used for web applications, separating managed code functionality between windows apps and web apps. Someone should write and article on the subject.

Hello jkirkerx,

Thanks for the reply.
So, is there no way that I can get logged in username??
Please give me some advice.
I have done everything and it still returns me "

NT AUTHORITY\IUSR

"

Thanks,
Raesa

Not that I'm aware of. If your running a vb, c# or c++ windows app you can, but on a web app, your going to get the IIS thread credentials that's running the web app.

If the web server app was programed to use windows authentication, and you login to the domain, you can probably get the current windows domain and user name.

I have a drop down list that is populated by reading the student's names that have less than 3 classes in a semester. It is also reading a class list that has a population of less than 10. I can get it to work if i ADD a NEW student and then that student has reached 3 classes it will remove his name from the drop down, and the same with the class when I click add it removes BOTH the student (if over 3) and the class (if more than 10). However .. Here is the problem. When I delete a student from the schedule it does not update the drop down list. I have several databinds() but it does not appear to fix things.

Ideally when it deletes a student from a class and let's say that student was formerly locked out (i.e. has 3 classes) - well then he has 2 and it should add his name if so to the drop down list (which is not updating). Thew same with CLASS since he dropped the class the count went down and if the class was full before it might not be now. Appreciate any insight you can offer. Weird how it works one way but not the other. In other words the grid is what is causing the problem - it updates but not the top part (drop down) even though I have databinds.

Here is the code:

C#

using System;
using System.Data;
using System.Data.OleDb;
using System.Web.UI.WebControls;

public partial class frmRegisterStudent : System.Web.UI.Page
{
    private void PopClass()
    {
        // Populate Class and add Please Select
        // Populate Student and add Please Select
        string path = Server.MapPath("eAcademy_DB.mdb");
        string connectionString = "PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=" + path;
        string commandText10 = "SELECT class_ID FROM tblClass WHERE class_ID NOT IN (SELECT class_ID FROM tblschedule GROUP BY class_ID HAVING COUNT(class_ID) >= 10)";

        var ds10 = new DataSet();

        using (var connection10 = new OleDbConnection(connectionString))
        using (var command = new OleDbCommand(commandText10, connection10))
        {
            // OleDbCommand uses positional, rather than named, parameters.
            // The parameter name doesn't matter; only the position.
            command.Parameters.AddWithValue("@p0", ddlstudID.SelectedValue);

            var adapter = new OleDbDataAdapter(command);
            adapter.Fill(ds10);
        }

        ddlclassSelect.DataSource = ds10;
        ddlclassSelect.DataTextField = "class_ID";
        ddlclassSelect.DataValueField = "class_ID";
        ddlclassSelect.DataBind();
        ddlclassSelect.Items.Insert(0, new ListItem("Please Select", "0"));
                      
            
    }
    private void PopStud()
    {
        // Populate Student and add Please Select
        string path = Server.MapPath("eAcademy_DB.mdb");
        string connectionString = "PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=" + path;
        //string commandText = "SELECT * from tblStudent";
        string commandText = "SELECT * FROM tblStudent where tblStudent.stud_id in (SELECT tblSchedule.stud_id FROM tblSchedule GROUP BY tblSchedule.stud_id HAVING count(tblSchedule.stud_ID) < 3)";
        var ds9 = new DataSet();

        using (var connection9 = new OleDbConnection(connectionString))
        using (var command = new OleDbCommand(commandText, connection9))
        {
            // OleDbCommand uses positional, rather than named, parameters.
            // The parameter name doesn't matter; only the position.
            command.Parameters.AddWithValue("@p0", ddlstudID.SelectedValue);

            var adapter = new OleDbDataAdapter(command);
            adapter.Fill(ds9);
        }

        ddlstudID.DataSource = ds9;
        ddlstudID.DataTextField = "stud_ID";
        ddlstudID.DataValueField = "stud_ID";
        ddlstudID.DataBind();
        ddlstudID.Items.Insert(0, new ListItem("Please Select", "0"));
        
    }
    private void CheckSession()
    {
        if (Session["SecurityLevel"] == null)
        {
            Response.Redirect("~/frmLogin.aspx");
        }

    }
    protected void Page_Load(object sender, EventArgs e)
    {
        CheckSession();

        if (!IsPostBack)
        {
            
            PopClass();
            PopStud();

        }
        else
        {
            ddlstudID.DataBind();
            ddlclassSelect.DataBind();
            
        }
    }
    protected void AddClass_Click(object sender, EventArgs e)
    {
        // Error Check so that Please Select is not there
        if (ddlstudID.SelectedValue == "0")
        {
            lblErrStudentName.Text = "Please Select a Student.";
            lblErrStudentName.Visible = true;
        }
        else
        {
            lblErrStudentName.Text = "";
            lblErrStudentName.Visible = false;
        }
        // Error Check so that Please Select is not there
        if (ddlclassSelect.SelectedValue == "0")
        {
            lblErrClassSelect.Text = "Please Select a Class.";
            lblErrClassSelect.Visible = true;
        }
        else
        {
            lblErrClassSelect.Text = "";
            lblErrClassSelect.Visible = false;
        }


        if (lblErrStudentName.Text == "" && lblErrClassSelect.Text == "")
        if (clsDataLayer.SaveSched(Server.MapPath("eAcademy_DB.mdb"),
            (Convert.ToString(ddlstudID.SelectedValue)),
            (Convert.ToString(ddlclassSelect.SelectedValue))))
        {
            txtVerifySaved.Text = "The information was saved.";
            txtVerifySaved.Visible = true;
            GridView1.DataBind(); // Refresh the bottom part.

            // Reset the index on all drop downs
            PopClass();
            PopStud();
            ddlstudID.SelectedIndex = 0;
            ddlclassSelect.SelectedIndex = 0;
        }
        else
        {
            // Make this visable to see
            txtVerifySaved.Text = "The information was NOT saved.";
            txtVerifySaved.Visible = true;
        }
    }
    protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
    {
        PopStud();
        PopClass();
        ddlstudID.SelectedIndex = 0;
        ddlclassSelect.SelectedIndex = 0;
        
    }
}

ADDENDUM ; Going to try moving most of the code to the datalayer and see if it works better.

modified 6-Jun-13 20:48pm.

FIXED!

I hard coded the Delete Command to the Grid like this:

C#

<asp:LinkButton runat="server" 
                                            CommandArgument='<%# Eval("class_ID")+ "&" + Eval("stud_ID") %>' 
                                            OnCommand="LinkButton_Click" Text="Delete">
                                        </asp:LinkButton>

In the code back did this:

C#

protected void LinkButton_Click(Object sender, CommandEventArgs e)
    {

        if (e.CommandArgument != null)
        {
            
            string MainString = e.CommandArgument.ToString();
            string[] Split = MainString.Split(new Char[] { '&' });
            //SHOW RESULT of SPLIT
            Session["ClassID"] = (Convert.ToString(Split[0]));
            Session["StudID"] =  (Convert.ToString(Split[1]));
                        
            clsDataLayer.RemoveSchedule(Server.MapPath("eAcademy_DB.mdb"),(String)Session["StudID"],(String)Session["ClassID"]);

            PopClass();
            PopStud();
            gvTeachers.DataBind();
            Session["ClassID"] = null;
            Session["StudID"] = null;    
        }

    }

AND Lastly in my clsdatalayer:

C#

public static void RemoveSchedule(String path, String StudX, String ClassX)
        {
            //declaring database variables to access the database Addressbook
            OleDbConnection dbConn = null;
            OleDbCommand dbCmd;
            OleDbDataReader dr;
            String strConnection;
            String strSQL;
            
            {
                strConnection = "PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=" + path;
                dbConn = new OleDbConnection(strConnection);
                dbConn.Open();
                strSQL = "DELETE * FROM tblSchedule WHERE (class_ID=? and stud_ID=?)";
                dbCmd = new OleDbCommand(strSQL, dbConn);
                dbCmd.Parameters.Add(new OleDbParameter("class_ID", ClassX));
                dbCmd.Parameters.Add(new OleDbParameter("stud_ID", StudX));
                dr = dbCmd.ExecuteReader();
                dr.Read();
                dbConn.Close();
                

            }
            
        }

Now to just add back the TRY Catch and it should be working nicely.

Hi All

1.I have to create a store procedure using 2 db'S
2.using the above sp I want to do crud operation

We heard you the first time.

Use the best guess

Hi All,

1.I need to join two database in a sp
2.I need to do all crud operation using that sp in c# asp.net

I am running a program which downloads data from yahoo finance. The program has 2 parts. Under Default.aspx I have the following code :

<%@ Page Language="C#" AutoEventWireup="true" 
    CodeBehind="Default.aspx.cs" Inherits="sample._Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
      "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Stock quote and chart from Yahoo in C#</title>
<script type="text/javascript" language="JavaScript">
    /// <summary>
    /// This function will be called when user clicks the Get Quotes button.
    /// </summary>
    /// <returns>Always return false.</returns>
    function SendRequest()
    {
        var txtSymbol = document.getElementById("txtSymbol");
        // Refresh the page.
        window.location = "default.aspx?s=" + txtSymbol.value;
        return false;
    }

    /// <summary>
    /// The functyion will be called when a keyboard key is pressed in the textbox.
    /// </summary>
    /// <param name="e">Onkeypress event.</param>
    /// <returns>Return true if user presses Enter key; otherwise false.</returns>
    function CheckEnter(e)
    {
        if ((e.keyCode && e.keyCode == 13) || (e.which && e.which == 13))
            // Enter is pressed in the textbox.
            return SendRequest();
        return true;
    }

    /// <summary>
    /// The function will be called when user
    // changes the chart type to another type.
    /// </summary>
    /// <param name="type">Chart type.</param>
    /// <param name="num">Stock number.</param>
    /// <param name="symbol">Stock symobl.</param>     
    function changeChart(type, num, symbol)
    {
        // All the DIVs are inside the main DIV
        // and defined in the code-behind class.
        var div1d=document.getElementById("div1d_"+num);
        var div5d = document.getElementById("div5d_" + num);
        var div3m = document.getElementById("div3m_" + num);
        var div6m = document.getElementById("div6m_" + num);
        var div1y = document.getElementById("div1y_" + num);
        var div2y = document.getElementById("div2y_" + num);
        var div5y = document.getElementById("div5y_" + num);
        var divMax = document.getElementById("divMax_" + num);
        var divChart = document.getElementById("imgChart_" + num);
        // Set innerHTML property.
        div1d.innerHTML = "1d";
        div5d.innerHTML="5d";
        div3m.innerHTML="3m";
        div6m.innerHTML="6m";
        div1y.innerHTML="1y";
        div2y.innerHTML="2y";
        div5y.innerHTML="5y";
        divMax.innerHTML="Max";
        // Use a random number to defeat cache.
        var rand_no = Math.random();
        rand_no = rand_no * 100000000;
        //  Display the stock chart.
        switch(type)
        {
        case 1: // 5 days
            div5d.innerHTML="5d";
            divChart.src = "http://ichart.finance.yahoo.com/w?s=" + 
                           symbol + "&" + rand_no;
            break;
        case 2: // 3 months
            div3m.innerHTML="3m";
            divChart.src = "http://chart.finance.yahoo.com/c/3m/" + 
                           symbol + "?" + rand_no;
            break;
        case 3: // 6 months 
            div6m.innerHTML = "6m";
            divChart.src = "http://chart.finance.yahoo.com/c/6m/" + 
                           symbol + "?" + rand_no;
            break;
        case 4: // 1 year
            div1y.innerHTML = "1y";
            divChart.src = "http://chart.finance.yahoo.com/c/1y/" + 
                           symbol + "?" + rand_no;
            break;
        case 5: // 2 years
            div2y.innerHTML = "2y";
            divChart.src = "http://chart.finance.yahoo.com/c/2y/" + 
                           symbol + "?" + rand_no;
            break;
        case 6: // 5 years
            div5y.innerHTML = "5y";
            divChart.src = "http://chart.finance.yahoo.com/c/5y/" + 
                           symbol + "?" + rand_no;
            break;
        case 7: // Max
            divMax.innerHTML = "msx";
            divChart.src = "http://chart.finance.yahoo.com/c/my/" + 
                           symbol + "?" + rand_no;
            break;
        case 0: // 1 day
        default:                
            div1d.innerHTML = "1d";
            divChart.src = "http://ichart.finance.yahoo.com/b?s=" + 
                           symbol + "&" + rand_no;
            break;
        }
    }
</script>    

</head>
<body>
    <form id="form1" runat="server">
    <div>
        <table width="100%" border="0" 
                 cellspacing="0" cellpadding="0">
            <tr valign="top">                                            
                <td style="font-family: Arial, Helvetica, sans-serif; 
                           font-size: 14px; color: #000; text-decoration: none;">
                    <input type="text" value="" id="txtSymbol" 
                        runat="server" onkeypress="return CheckEnter(event);" />
                    <input type="button" value="Get Quotes" 
                        onclick="return SendRequest();" />
                    <br />
                    <span style="font-family: Arial, Helvetica, sans-serif; 
                                 font-size: 11px; color: #666;">
                        e.g. "YHOO or YHOO GOOG"
                    </span>
                    <%if (m_symbol != "") {%>                        
                        <div id="divService" runat="server">
                        <!-- Main DIV: this DIV contains text and DIVs 
                                       that displays stock quotes and chart. -->
                        </div>
                    <%}%>
                </td>    
            </tr>
        </table>
    </div>
    </form>
</body>
</html>

And under Default.aspx page I have the following code:
<%@ Page Language="C#" AutoEventWireup="true" 
    CodeBehind="Default.aspx.cs" Inherits="sample._Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
      "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Stock quote and chart from Yahoo in C#</title>
<script type="text/javascript" language="JavaScript">
    /// <summary>
    /// This function will be called when user clicks the Get Quotes button.
    /// </summary>
    /// <returns>Always return false.</returns>
    function SendRequest()
    {
        var txtSymbol = document.getElementById("txtSymbol");
        // Refresh the page.
        window.location = "default.aspx?s=" + txtSymbol.value;
        return false;
    }

    /// <summary>
    /// The functyion will be called when a keyboard key is pressed in the textbox.
    /// </summary>
    /// <param name="e">Onkeypress event.</param>
    /// <returns>Return true if user presses Enter key; otherwise false.</returns>
    function CheckEnter(e)
    {
        if ((e.keyCode && e.keyCode == 13) || (e.which && e.which == 13))
            // Enter is pressed in the textbox.
            return SendRequest();
        return true;
    }

    /// <summary>
    /// The function will be called when user
    // changes the chart type to another type.
    /// </summary>
    /// <param name="type">Chart type.</param>
    /// <param name="num">Stock number.</param>
    /// <param name="symbol">Stock symobl.</param>     
    function changeChart(type, num, symbol)
    {
        // All the DIVs are inside the main DIV
        // and defined in the code-behind class.
        var div1d=document.getElementById("div1d_"+num);
        var div5d = document.getElementById("div5d_" + num);
        var div3m = document.getElementById("div3m_" + num);
        var div6m = document.getElementById("div6m_" + num);
        var div1y = document.getElementById("div1y_" + num);
        var div2y = document.getElementById("div2y_" + num);
        var div5y = document.getElementById("div5y_" + num);
        var divMax = document.getElementById("divMax_" + num);
        var divChart = document.getElementById("imgChart_" + num);
        // Set innerHTML property.
        div1d.innerHTML = "1d";
        div5d.innerHTML="5d";
        div3m.innerHTML="3m";
        div6m.innerHTML="6m";
        div1y.innerHTML="1y";
        div2y.innerHTML="2y";
        div5y.innerHTML="5y";
        divMax.innerHTML="Max";
        // Use a random number to defeat cache.
        var rand_no = Math.random();
        rand_no = rand_no * 100000000;
        //  Display the stock chart.
        switch(type)
        {
        case 1: // 5 days
            div5d.innerHTML="5d";
            divChart.src = "http://ichart.finance.yahoo.com/w?s=" + 
                           symbol + "&" + rand_no;
            break;
        case 2: // 3 months
            div3m.innerHTML="3m";
            divChart.src = "http://chart.finance.yahoo.com/c/3m/" + 
                           symbol + "?" + rand_no;
            break;
        case 3: // 6 months 
            div6m.innerHTML = "6m";
            divChart.src = "http://chart.finance.yahoo.com/c/6m/" + 
                           symbol + "?" + rand_no;
            break;
        case 4: // 1 year
            div1y.innerHTML = "1y";
            divChart.src = "http://chart.finance.yahoo.com/c/1y/" + 
                           symbol + "?" + rand_no;
            break;
        case 5: // 2 years
            div2y.innerHTML = "2y";
            divChart.src = "http://chart.finance.yahoo.com/c/2y/" + 
                           symbol + "?" + rand_no;
            break;
        case 6: // 5 years
            div5y.innerHTML = "5y";
            divChart.src = "http://chart.finance.yahoo.com/c/5y/" + 
                           symbol + "?" + rand_no;
            break;
        case 7: // Max
            divMax.innerHTML = "msx";
            divChart.src = "http://chart.finance.yahoo.com/c/my/" + 
                           symbol + "?" + rand_no;
            break;
        case 0: // 1 day
        default:                
            div1d.innerHTML = "1d";
            divChart.src = "http://ichart.finance.yahoo.com/b?s=" + 
                           symbol + "&" + rand_no;
            break;
        }
    }
</script>    

</head>
<body>
    <form id="form1" runat="server">
    <div>
        <table width="100%" border="0" 
                 cellspacing="0" cellpadding="0">
            <tr valign="top">                                            
                <td style="font-family: Arial, Helvetica, sans-serif; 
                           font-size: 14px; color: #000; text-decoration: none;">
                    <input type="text" value="" id="txtSymbol" 
                        runat="server" onkeypress="return CheckEnter(event);" />
                    <input type="button" value="Get Quotes" 
                        onclick="return SendRequest();" />
                    <br />
                    <span style="font-family: Arial, Helvetica, sans-serif; 
                                 font-size: 11px; color: #666;">
                        e.g. "YHOO or YHOO GOOG"
                    </span>
                    <%if (m_symbol != "") {%>                        
                        <div id="divService" runat="server">
                        <!-- Main DIV: this DIV contains text and DIVs 
                                       that displays stock quotes and chart. -->
                        </div>
                    <%}%>
                </td>    
            </tr>
        </table>
    </div>
    </form>
</body>
</html>

When I run the program , I get the bundles elements is not declared and txtSymbol and divService does not exist in the current context.

Hi

I would like to add live Tv Chanel in asp.net web application can anyone suggest me how can i approach to do so... plz... Smile | :)

i searched in Google but no luck. i got only saved video files streaming but i am searching for LIVE STREAMING...

hey.. firstly you ned some sort of streaming software. such as Broadcam,Windows Movie maker,

that will allow you to stream video and moreover, static IP is also needed for the purpose.

Chetan
facebook.com/thechetantalwar

Thank You Chethan.. Smile | :)

Hi,

What is the logic/meaning behind every character used in this validationExpression like \b \w [..] (-a) etc.

Please explain.
Thanks in advance.

It's a Regular Expression. The full documentation is available on MSDN:
http://msdn.microsoft.com/en-us/library/az24scfc.aspx[^]

"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer

Thanks Richard...

I am running into a problem here, and I have no code needed or that requires debugging. I am looking for more of an idea to solve this issue, so here it is.

I have a *.exe that is a command prompt utility that generates images. What I am doing is using this utility for my asp.net website. In the background I do processing for each date in a asp.net calendar. If the image doesn't exist in the images directory for that date, Calendar_DayRender calls the backend to use the exe via Process. The image creation works great. As does the loading, if the image was already created in a previous session by any other user.

The problem is that the images are being created too quicky and I cannot load the image because when I try to add the Image to the cell, it was not created quickly enough. Any ideas on how I can solve this timing issue?

Check for the existence of the image file in the main thread before you send the reply to the client.

Make the image request synchronous? How are you requesting the image in the first place? If you do it with a tag, the browser should wait for a response.

I've done this in the past...

If the myImageGenerator.aspx page streams back an image, the browser will display it. I learned this technique from an OLD article on here about Captcha - the image streaming technique is still valid.

A CAPTCHA Server Control for ASP.NET[^]

I have been creating a smaller scale MUCH SIMPLIFIED version of a registration system that assumes classes are taught once a week. This system already checks if a teacher has taught 3 classes to not select him for further classes. But I need to make sure it also checks that the room is not already chosen for a class previous during the time it wants.

What I have so far selects rooms and shows them in a drop down list, but I am able to make it show all room less everything chosen so far but it does not take into consideration the time and day of the week and so it is eliminating anything chosen, not just for the day of the week and the start_Hour and end_Hour times.

// Populate Room and add Please Select
            // This shows ALL Rooms ---> string commandText1 = "SELECT * FROM tblRoom";\
            // Below shows ALL rooms minus any chosen before but does not consider day of the week (week_Day) or (start_Time and end_Time) of the class.
            string commandText1 = "SELECT * FROM tblRoom WHERE NOT EXISTS (SELECT * FROM tblClass WHERE tblRoom.room_Num = tblClass.room_Num)";
           


            var ds1 = new DataSet();

            using (var connection = new OleDbConnection(connectionString))
            using (var command = new OleDbCommand(commandText1, connection))
            {
                // OleDbCommand uses positional, rather than named, parameters.
                // The parameter name doesn't matter; only the position.
                command.Parameters.AddWithValue("@p0", ddlRoom.SelectedValue);

                var adapter = new OleDbDataAdapter(command);
                adapter.Fill(ds1);
            }

            ddlRoom.DataSource = ds1;
            ddlRoom.DataTextField = "room_Num";
            ddlRoom.DataValueField = "room_Num";
            ddlRoom.DataBind();
            ddlRoom.Items.Insert(0, new ListItem("Please Select", "0"));
            ddlRoom.Items.Insert(1, new ListItem("TBD", "TBD"));
        }

    }

tblRoom consists of tblRoom.room_Num (Key) TextString with Room#

tblClass consists of tblClass.room_Num (FK) TextString,
CourseID (FK) from tblCourse, week_Day which is the Day Of the Week (Monday, Tueday, Wednesday, Thursday, Friday or Saturday). start_Hour and end_Hour for when the class begins and ends.

What I am looking for is to improve the select command above so it can use week_Day = ? (ddlweekDay.SelectedValue) start_Hour (ddlstarthour.selectedvalue), end_Hour (ddlendHour.SelectedValue) OR to "remove" it from the drop down after it populates but before it shows the user. Hence perhaps a subroutine it can run called checkavailablity() where it might pass these parameters when all the time fields have been filled out or something. I know I can remove a line from the drop down and do it by naming the courseID or something? This is at least my next approach idea.

This is a very simplified version and has simple assumptions, not need to over think this. There is no gym class, and each class room is just that a class room. I just want to be able to schedule the classes -- not adding students as yet.

Seems difficult to give you a precise answer without knowing more about the database.

From my point of view, but I might be biased as I come more from a SQL background than many, I would create a SQL View, taking parameters (stored procedure) returning all ClassRooms available between 2 datetime (start and end), and I would do my select against this view.

Also, as I guess classes starts and end at a fixed hour, instead of using a whole datetime twice, I would build a fixed table with ID values, for example, from 8 to 8:45 AM = #1, from 9 to 9:45 = #2, and so on...

Just some ideas....

Bernard Grosperrin
BGSoftFactory

I am brainstorming ideas for an web browser WYSIWYG text editor for LED like displays. The editor will show a matrix of bulbs. As the user types, the bulbs corresponding to the keys pressed will be turned on. The editor will support backspace and most basic text editor functions. The displays are also of different sizes (pixel height, width, etc) and support different fonts.

I've seen where javascript supports key up/down events. What I am focusing on right now is the edittable pixel display.

The two ideas I have right now are

1) A table with each cell filled with an OffBulb.png. As the user types, javascript determines the appropriate cells to be changed to an OnBulb.png.

2) The server creates .png for all supported characters (~200 chars - a lot of images) and as the user types, the character pngs are layed out in the container one after the other.

Does anyone have any ideas?

The platform will be .NET either MVC or possible WebForms.

You mean a look-up table right? You put your 200 characters in an array of objects which each hold the name of the character and the image for the character. THAT array NEVER changes!

When the user enters the characters they want, you create an array for the user input, but don't copy the values from the 200-character array - copy the indexes. So, in memory, the message looks like this...

53 41 4c 45 20 6f 6e 20 44 56 44 73 20 54 4f 44 41 59 21 - which I would bet is exactly what the sign stores too.

So "the character pngs are layed out in the container one after the other." isn't the right way to do it - just put the reference numbers in there. Making copies of the character set is wasteful, and LED signs don't have a ton of memory - you should emulate that behavior in your web interface.

And when you're done... please fix Bubba Chino's sign... it has been flashing "LED SIGN!" for two years ever since he bought it Smile | :)