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hi! i am using vb.net 2003. but now i have started getting an error "object reference not set to an instance of an object" and that too as soon as i start coding. as soon as i enter the editor, the first thing i do select an "oledb connection control" from the toolbox. and next in the property tab of the oledbconnection, as soon as i select the connectionstring value, the abovementioned error occurs. i just can't understand y this is happening as i haven't even started coding! ne1 ever encountered this error b4???
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Prem Ranjan wrote: ne1 ever encountered this error b4???
Please stick to English...
What you can do is open a second instance of the IDE, attach the debugger to the first instance, and see where you end up when it crashes.
Christian Graus - Microsoft MVP - C++
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )
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Christian Graus wrote: stick to English...
Text speak is turned off right now...b4 didn't compile for a minute there
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
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hi guys
i have a string
like "12007" or "112007"
in this string last four characters denotes to a specific year and the rest shows month ,
i want to get a the month either ir is 1 or 12 or 10 ,, i cannot use sunstring because i am not sure about its lenth it might me 1 or two , so how could i get the exazct month ,,,
thansk in advance
hello
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Unless someone sticks the day of the month in there, then you got some trouble.
You have to assume that the last four are the year, then anything before that is going to be the month. Assuming the day of month isn't going to be there, you will have to check the length of the string. If it is 5 then you have one digit for the month, else if the length is 6, then you have two digits for the month. Find the length of the string first, then you can use SubString(....) to pick it apart.
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
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Why not look at the total length of the string then subtract 4 (the number of digits for the year portion) and use that data to know the rest?
Its just working backwards.
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chop last 4 chars and parse, I would say.
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Can someone please help me filling a DataGrid without a DataSource. I'm used to work with a component called the True DBGrid made by ComponentOne for VB6, and it was a walk in the park to change the cells' value. Surely there's a way to modify the values without a source, right?
Thanks in advance!
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I Don't know if I understand your question correcly, but if you are using VS2005, and a DataGridView control, you can do this:
'Drop the control on your form
'Add two columns
Me.DataGridView1.Columns.Add("Col1", "FirstColName")
Me.DataGridView1.Columns.Add("Col2", "SecondColName")
'Add some rows - 5 in this case
Me.DataGridView1.Rows.Add(5)
'Modify the Data in the control
Me.DataGridView1.Item(0, 0).Value = "Hello" 'Row 0, Column 0
Me.DataGridView1.Item(0, 1).Value = "Dude" 'Row 1, Column 0
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You could do how Richard described, but if you're going to save the data in the grdi, you'd be better off binding the grid to a DataTable you create. The DataTable object can save, and load, the data into/from an XML file without a pile of code on your part.
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Hi, would you please explain the two lines of code below that are high lighted.
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(qry, con);
da.Fill(ds);
ListBox1.DataSource = ds;
ListBox1.DataValueField = "SingerID";
ListBox1.DataTextField = "Singer";
ListBox1.DataBind();
Are "SingerID" and "Singer" the names of fields in a database. The comment to the right of "Singer"; says that the name of singers will be displayed. How will it be displayed, in grid or something else? Thanks for your help.
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SingerID is the id (probably primary key) of the Singer, and Singer contains the text of the name. What happens is if the user selects a name from the listbox, then the SelectedValue property of the listbox is the corresponding SingerID for that particular name.
"I've seen more information on a frickin' sticky note!" - Dave Kreskowiak
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Suppose instead of having Singer and SingerID as the names of the fields in the database, I have ResumeID and Resumes as the names, and Resumes contains resumes of different people. Can I use the same technique that was used to display the content Singer to display the content of Resumes if Resumes is of type nvarchar or text? Thanks for responding.
-- modified at 22:32 Monday 23rd July, 2007
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Singer looks as if it is the field in the database holding the names of the singers. In your case, you can change SingerID to ResumeID , and Singer to Resumes . It should work.
"I've seen more information on a frickin' sticky note!" - Dave Kreskowiak
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Hi, please help I've been wrestling with this for a very long time and its not working. The following is my code.
<br />
<br />
Private Sub ListBox2_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox2.SelectedIndexChanged<br />
<br />
Dim myCon As OdbcConnection<br />
Dim i As Integer<br />
Dim cmd As OdbcCommand<br />
For i = 0 To ListBox2.Items.Count - 1<br />
If ListBox2.Items(i).Selected Then<br />
<br />
myCon = New OdbcConnection("Driver={MySQL ODBC 3.51 Driver};Server=myServer;Database=myDatabase;User=myUserassword=myPass;Option=3;")<br />
cmd = New OdbcCommand("SELECT * FROM myTable where Professions = '" & ListBox2.Items(i).Text & "'")<br />
<br />
End If<br />
Next<br />
If Not IsNothing(myCon) Then<br />
myCon.Open()<br />
<br />
cmd.Connection = myCon<br />
<br />
Dim ds As New DataSet<br />
<br />
Dim ad As New OdbcDataAdapter(cmd)<br />
<br />
ad.Fill(ds)<br />
<br />
Me.ListBox2.DataSource = ds<br />
<br />
Me.ListBox2.DataTextField = "ResumesID"<br />
Me.ListBox2.DataTextField = "Resumes"<br />
Me.ListBox2.DataBind()<br />
<br />
End If<br />
End Sub<br />
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ASPnoob wrote: User=myUserassword=myPass;
This might be your problem. Please describe the error you are having.
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
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ASPnoob wrote: Me.ListBox2.DataTextField = "ResumesID"
Me.ListBox2.DataTextField = "Resumes"
For starters you're setting the DataTextField 2 times. Once should be DataTextField (Resumes) and the other should be DataValueField (ResumeID)
"It's only that urgent if you have to pee."
Dave Kreskowiak
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Psycho-*Coder*-Extreme wrote: For starters you're setting the DataTextField 2 times
Oops, how did I miss that one?
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
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Paul Conrad wrote: Oops, how did I miss that one?
Not enough coffee?
"Well yes, it is an Integer, but it's a metrosexual Integer. For all we know, under all that hair gel it could be a Boolean."
Tom Welch
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Yeah, Dr. Pepper's wearing out here
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
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Well you could always hook yourself up to a Dr. Pepper IV, then install a serial port to the back of your head, then even when you sleep you can answer questions here on CP
"Well yes, it is an Integer, but it's a metrosexual Integer. For all we know, under all that hair gel it could be a Boolean."
Tom Welch
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Psycho-*Coder*-Extreme wrote: hook yourself up to a Dr. Pepper IV, then install a serial port to the back of your head, then even when you sleep you can answer questions here on CP
That would be cool, kind of like The Matrix sort of thing
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
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The truly scary part is I actually think of things like that, how to find a way to install a serial port onto the back of my head and stuff, does that make me weird?
"Well yes, it is an Integer, but it's a metrosexual Integer. For all we know, under all that hair gel it could be a Boolean."
Tom Welch
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Psycho-*Coder*-Extreme wrote: does that make me weird?
Nah, I've thought of how cool it would be to make a world like a Star wars world or Matrix kind of thing.
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
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Hi, please help I've been wrestling with this for a very long time and its not working. The problem is it doesn't generate any errors, no exception was thrown. The following is my code.
<br />
<br />
Private Sub ListBox2_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox2.SelectedIndexChanged<br />
<br />
Dim myCon As OdbcConnection<br />
Dim i As Integer<br />
Dim cmd As OdbcCommand<br />
For i = 0 To ListBox2.Items.Count - 1<br />
If ListBox2.Items(i).Selected Then<br />
<br />
myCon = New OdbcConnection("Driver={MySQL ODBC 3.51 Driver};Server=myServer;Database=myDatabase;User=myUserassword=myPass;Option=3;")<br />
cmd = New OdbcCommand("SELECT * FROM myTable where Professions = '" & ListBox2.Items(i).Text & "'")<br />
<br />
End If<br />
Next<br />
If Not IsNothing(myCon) Then<br />
myCon.Open()<br />
<br />
cmd.Connection = myCon<br />
<br />
Dim ds As New DataSet<br />
<br />
Dim ad As New OdbcDataAdapter(cmd)<br />
<br />
ad.Fill(ds)<br />
<br />
Me.ListBox2.DataSource = ds<br />
<br />
Me.ListBox2.DataTextField = "ResumesID"<br />
Me.ListBox2.DataTextField = "Resumes"<br />
Me.ListBox2.DataBind()<br />
<br />
End If<br />
End Sub<br />
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