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In a C# 2008 application, I have the following linq to sql statement setup so far.
eDataContext eData = new eDataContext();
var eSelect = (from iw in eData.Ibooks
join ip in etData.IPack on iw.P_ID equals ip.P_ID
join eTrack in eData.eRPT_Trans
on ip.TNum equals eTrack.P_ID
where ip.TNum == packageId
select iw).FirstOrDefault();
I want to obtain values from the 3 different tables listed in the statement above
How do I change the linq statement above so that I can obtain data from all three tables?
Thus can you show me how to obtain data from all 3 tables?
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As part of your select statement, you can put any fields from the three tables in there, just as if you were doing a select in SQL. Ex: Select {iw, ip, eTrack}. The best thing would be to use select fields instead of all of the fields from all three tables.
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eDataContext eData = new eDataContext();
var eSelect = (from iw in eData.Ibooks
join ip in etData.IPack on iw.P_ID equals ip.P_ID
join eTrack in eData.eRPT_Trans
on ip.TNum equals eTrack.P_ID
where ip.TNum == packageId
select new
{
iw.P_ID,
ip.P_ID,
eTrack.P_ID
/*
Other fields
*/
}
).FirstOrDefault();
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Hi all,
In my windows form I have many group-boxes with text-boxes.
I am changing the back color of the text-boxes whenever a text-box has or looses focus.
This works OK.
I also want to add a help button in the group-box when a text-box in this group-box has focus,
but my help button is added three times?
This is the code I use:
private void control_Settings()
{
Button buttonHelp = new Button();
buttonHelp.BackColor = System.Drawing.Color.Transparent;
buttonHelp.Image = Properties.Resources.HelpButtonImage;
buttonHelp.Dock = DockStyle.Right;
buttonHelp.Name = "buttonHelp";
buttonHelp.Size = new System.Drawing.Size(25, 25);
buttonHelp.UseVisualStyleBackColor = false;
buttonHelp.Click += new System.EventHandler(this.buttonHelp_Click);
foreach (Control gb in Controls)
{
if (gb is GroupBox)
{
GroupBox grpbx = (GroupBox)gb;
foreach (Control t in grpbx.Controls)
{
TextBox textBox = t as TextBox;
if (textBox != null)
{
textBox.Enter += delegate(object sender, EventArgs eventArgs)
{
((TextBox)sender).BackColor = Color.Gold;
Control pToAd = ((TextBox)sender).Parent;
if(!pToAd.Controls.Contains(buttonHelp))pToAd.Controls.Add(buttonHelp);
};
textBox.Leave += delegate(object sender, EventArgs eventArgs)
{
Control pToRemove = ((TextBox)sender).Parent;
((TextBox)sender).BackColor = Color.White;
pToRemove.Controls.Remove(buttonHelp);
};
}
}
}
}
}
Thanks in advance,
Groover
0200 A9 23
0202 8D 01 80
0205 00
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(I changed some of the naming so I could understand the flow better)
using System;
using System.Drawing;
using System.Windows.Forms;
public partial class FormMain : Form
{
public Form1()
{
InitializeComponent();
ControlSettings();
}
private void ControlSettings()
{
Button buttonHelp = new Button();
buttonHelp.BackColor = System.Drawing.Color.Transparent;
buttonHelp.Dock = DockStyle.Right;
buttonHelp.Name = "buttonHelp";
buttonHelp.Size = new System.Drawing.Size(25, 25);
buttonHelp.UseVisualStyleBackColor = false;
foreach (Control control in Controls)
{
if (control is GroupBox)
{
GroupBox groupBox = (GroupBox)control;
foreach (Control nestedControl in groupBox.Controls)
{
TextBox textBox = nestedControl as TextBox;
if (textBox != null)
{
textBox.Enter += delegate(object sender, EventArgs eventArgs)
{
((TextBox)sender).BackColor = Color.Gold;
Control parent = ((TextBox)sender).Parent;
parent.Controls.Add(buttonHelp);
};
textBox.Leave += delegate(object sender, EventArgs eventArgs)
{
Control parent = ((TextBox)sender).Parent;
((TextBox)sender).BackColor = Color.White;
parent.Controls.Remove(buttonHelp);
};
}
}
}
}
}
}
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Thank You Dave for Your effort,
Knowing there is nothing wrong with my code, I found there is something strange.
ControlSettings()
was also called in:
private void Form1_Resize(object sender, System.EventArgs e)
{
control_Settings();
this.Invalidate();
}
to do some other settings.
If I remove these other settings it is still not working,
If I remove the form resizing it is working OK??
I do not do any resizing so why is the form resize event breaking my control_Settings??
0200 A9 23
0202 8D 01 80
0205 00
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Then remove either control_Settings(); from the resize handler, or stop handling the event if you don't need it.
I added the call only to the constructor as this is the type of code that would normally only be run once.
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I agree with Dave that the code presented works for placing and removing a button. Of course as soon as you try to click on it, the textbox loses focus and the button disappears!
Alan.
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 Yeah, I noticed that too - but if that's what the OP wants...
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Hi Alan,
You are absolutely right, but I had to get it working first.
I moved the
buttonHelp.Click += new System.EventHandler(buttonHelp_Click);
to the textBox.enter delegate and modified the textBox.leave to:
textBox.Leave += delegate(object sender, EventArgs eventArgs)
{
Control pToRemove = ((TextBox)sender).Parent;
((TextBox)sender).BackColor = Color.White;
if (!pToRemove.ContainsFocus)
{
pToRemove.Controls.Remove(buttonHelp);
buttonHelp.Click -= new System.EventHandler(this.buttonHelp_Click);
}
};
Return focus to the control is handled in the buttonHelp.Click event handler.
But there is still the question why placing a call to Control_Settings in the Form.resize event,
that is never fired, makes the helpbutton control appear three times??
0200 A9 23
0202 8D 01 80
0205 00
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Just an alternative way of thought.
I would have added the help buttons and made them invisible. When the textbox receives focus I would make them visible, etc...
I think it would be easier to develop, easier to maintain and faster at runtime.
hope this helps.
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How FingerPrint Device uses zkemkeeper.dll to get ID of each user print it's finger in Device
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osama_hagrass wrote: How FingerPrint Device uses zkemkeeper.dll to get ID
We don't know "how" it does that, since we don't have the blueprint of the hardware, nor the source to the dll.
Looking for this[^] tutorial?
Bastard Programmer from Hell 
if you can't read my code, try converting it here[^]
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I have a question about the C# 2008 statement listed below:
string[] PkgIDs = rData.details.Where(c => c.batch_id == batchID).Select(c => c.Package_ID).Distinct().ToArray();
foreach (string PkgID in PkgIDs)
{
}
I would want to make certain an exception would not be generated in this situation.
If there is nothing selected for the PKgIDs [] table, do I need to to any check for this condition? If so, what would the check be?
Would you show me what code I would need to add?
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Based on what you've posted so far, there is no exception possible. But, since we can't see the code that declared these types, the details collection, how it's populated, ..., we really couldn't tell you for sure.
But, if the Select returns no ID's, the array will come back empty and the foreach iterating over it won't do anything.
You don't have to change this code at all.
Next time, you might want to try testing the code with test data specifically designed to try and break it.
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sc steinhayse wrote: I would want to make certain an exception would not be generated in this situation
Look up each command in the documentation, see if they CAN throw an exception. For example, the Distinct[^] method does not throw anything, but ToArray[^] might throw an ArgumentNullException.
sc steinhayse wrote: Would you show me what code I would need to add?
None, since you can't handle the exception locally (in this example). Have it propagate to the general exception-handler, and log it there.
Bastard Programmer from Hell
if you can't read my code, try converting it here[^]
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string[] PkgIDs = rData.details.Where(c => c.batch_id == batchID).Select(c => c.Package_ID).Distinct().ToArray();
if(PkgIDs.Count > 0)
{
foreach (string PkgID in PkgIDs)
{
}
}
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Totally unnecessary, foreach can iterate over a zero size collection without any problem.
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Write unit tests for the situations you are worried about and see if the result is correct?
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I need to write a C# 2010 windows service that will check for new files in a specified directory path . Can you tell me how to accomplish this goal?
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rachel_m wrote: Can you tell me how to accomplish this goal?
By writing the service.
Seriously, what is it that you are having trouble with?
The difficult we do right away...
...the impossible takes slightly longer.
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sorry accidently posted a weong message
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Using the FileSystemWatcher[^] control. There's a full example on the bottom of the page, assuming a normal winapp, not a service.
Bastard Programmer from Hell
if you can't read my code, try converting it here[^]
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Hi All,
In C#, How To Send A Hyperlink Using Query String Method.
I have developing a web application of user enter enters the personal data. That information has sent to admin mail with approve/reject link button.
When the Admin click the approve link, it has approve.aspx page with the user id as query string to update the db as approved. otherwise rejected.
I can try the following code.
mail.Subject = "New User";
mail.Body = "<p>Dear Sir, <br><br> " + txtfname.Text + " " + txtlname.Text + ", has raised a requisition that needs your approval. <br><br><br> Please click to [<a href='http://localhost:1240/IMA/Approve.aspx?id="+tt+"'> Approve</a> ] [<a href='Reject.aspx'>Reject</a> ] the request. <br> <br> <br> <b>Note</b> : Please do not reply. This e-mail has been auto-generated.</p>";
mail.IsBodyHtml = true;
In the mail i have move the mouse over the approve link it shows http://.../approve.aspx?id=1, but click the appove link
it shows <a href="http://.../id=1.
I don't know why.
Please help me out.
Thanks in advance,
Murugavel S
modified 6-Oct-12 20:54pm.
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Check the source of mail message to see if link renders correctly.
No more Mister Nice Guy... >: |
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