C# Discussion Boards - CodeProject

19-Dec-06 4:03

Hi,

I get this error: ArgumentOutOfRangeException

In this line:

this.Invoke(new DelA(delegateA), new object[] { s });

This is the environment of this code:

void delegateA(string s)
{
if (this.InvokeRequired)
{
this.Invoke(new DelA(delegateA), new object[] { response });
}
}

I've tried a few things to fix this, but im running out of suggestions.

Any suggestions anyone?

Thanks in advance!

Martin#19-Dec-06 4:21

19-Dec-06 4:21

Hello,

Is "response" a string?
Does youre DelA have an string parameter too?

Martin

Yustme19-Dec-06 4:24

19-Dec-06 4:24

Hi,

Yes on both questions.

Martin#19-Dec-06 4:37

19-Dec-06 4:37

Hello,

Could you post the full code of youre method and the delegate?

Martin

Yustme19-Dec-06 20:46

19-Dec-06 20:46

Hi,

I get this error in run time, by the way.

Here is the code:

void delegateA(string s)
{
if (this.InvokeRequired)
{
this.Invoke(new DelA(delegateA), new object[] { s });
}

else
{
if (this.itemscounter < this.totalitems)
{
this.itemscounter++;
}
}
}

This is the code where the the delegate listens to:

if (this.DelA != null)
{
this.DelA(this.bufferofserialport);
}

When i change the "< this.totalitems" to "< this.totalitems - 1", its not showing up the error.

But than its not completing till the end of the items in my listbox.

Thanks in advance!

Martin#19-Dec-06 23:09

19-Dec-06 23:09

Hello,

Are you using "itemscounter" for an access of an array somewhere?
for example:
xxx[itemscounter]
or
for(int i=0;i<=itemscounter;i++){ xxx[i]....)

Martin

Yustme19-Dec-06 23:22

Re: ArgumentOutOfRangeException delegate [modified]

19-Dec-06 23:22

Hi,

yes an ArrayList.

I filled the array with items with the for statement.

And using it now like xxx[itemscounter].

And in the if statement i go to the next item in the array.

Martin#19-Dec-06 23:38

Dataset/DataTable with DataGrid (local database only!)

19-Dec-06 23:38

Hello,

So it looks like the problem is here.

I guess if you depug the for statement you maybe find out that you whant to access a index which is out of range.

Maybe you just have to change some code from:
for(int x=0;x<=y;x++)
to:
for(int x=0;x<y;x++)

Hope that helps!

All the best,

Martin

Blubbo19-Dec-06 3:38

Blubbo

19-Dec-06 3:38

I'm trying to find good example for DataGrid (could be with DataSet example) with local database... I do not want example with SQLserver (which I have seen in many 'net sites), just local database.

Thanks! Confused | :confused:

Re: Dataset/DataTable with DataGrid (local database only!)

Private_Void19-Dec-06 7:43

Private_Void

19-Dec-06 7:43

What type of database is your local database?

Re: Dataset/DataTable with DataGrid (local database only!)

Blubbo19-Dec-06 7:49

Blubbo

19-Dec-06 7:49

I'm looking into simple 2 columns (name of variable, and Interpreted Data)... the interpreted data would be the translation of the raw hex data from a raw data line on file. Since that there are many lines (could be up to 3000 lines in all), wonder if I could set up the dataset to work with datagrid so i can view the data page by page by clicking "next" button?

Hope that clears up.

Re: Dataset/DataTable with DataGrid (local database only!)

Private_Void19-Dec-06 8:39

Private_Void

19-Dec-06 8:39

I am beginning to understand what your datasource is / looks like. Could you please send me an example of a row of data or two rows of data and I am sure I can assist you.

Re: Dataset/DataTable with DataGrid (local database only!)

Blubbo19-Dec-06 8:53

Blubbo

19-Dec-06 8:53

Ok.. to clarify what the datasource looks like... (both are string value).
I'm not sure how to set up the dataset so i can look on the next set of data.

from the first row of raw data would have:

Name Interpreted_Value
Color_Used Cyan
Install_Date 12/21/99
Error_Code 848-323

Next row from raw data:

Name Interpreted_Value
Color_Used Magenta
Install_Date 3/21/93
Error_Code 239-772

Next row from raw data:
Name Interpreted_Value
Color_Used Magenta
Install_Date 1/2/03
Error_Code None

Re: Dataset/DataTable with DataGrid (local database only!)

Private_Void19-Dec-06 9:47

Private_Void

19-Dec-06 9:47

The data in file C:\DataSource.txt from code Looks exactly like below....
Magenta,1/2/03,XDSDF
Blue,1/2/05,None

//I know this is kind of messy but i just slapped it together. let me know if you have any questions.

StreamReader s;
string[] columns = {"Color_Used","Install_Date","Error_Code"};
DataSet ds = new DataSet();
grvMain.DataSource = ds;
ds.Tables.Add("tblMain");
for (int i = 0; i < columns.Length; i++)
{
ds.Tables["tblMain"].Columns.Add(columns[i]);
}
string sFieldDelimiter = ",";
string sRowDelimiter = "\r\n";
s = new StreamReader(@"C:\DataSource.txt");
string sAllData = s.ReadToEnd();
string[] sRowsColSplit = sAllData.Split(sRowDelimiter.ToCharArray());

foreach (string row in sRowsColSplit)
{
if (row != "")
{
string[] rows = row.Split(sFieldDelimiter.ToCharArray());
ds.Tables["tblMain"].Rows.Add(rows);
}
}
grvMain.DataBind();

DataGridView and new rows

Wjousts19-Dec-06 3:25

Wjousts

19-Dec-06 3:25

I have a collection (IList) of custom objects bound to a DataGridView. When you click on the * line to create a new row the DataGridView automatically creates a new object for you to edit. When it does this it calls the default constructor. What I would like to do is intercept this process so that I can either call a different constructor or else do some extra initialization before the DataGridView tries to bind to it. Is there a way to do this? The RowsAdded and UserAddedRow event both fire too late. Which method is the DataGridView calling to create a new row? I don't think it's actually getting added to the collection until the user edits the row.

Thanks

Re: DataGridView and new rows

Lisa Jorgensen23-Dec-06 16:18

Lisa Jorgensen

23-Dec-06 16:18

One approach is to add a handler for the BindingSource's AddingNew event. E.g.:

InitializeGrid()
{
    // Create sample List of custom objects. First object uses a non-default
    // constructor, the second uses the default (no reason, just seemed
    // like something to do in the example).

    List<CustomItem> sourceList = new List<CustomItem>();
    CustomItem firstItem = new CustomItem("Special content");
    sourceList.Add(firstItem);
    CustomItem nextItem = new CustomItem();
    sourceList.Add(nextItem);

    // Create the BindingSource, add the list, and add an event handler
    // for the AddingNew event.

    BindingSource bindingSource = new BindingSource();
    bindingSource.DataSource = sourceList;
    bindingSource.AddingNew += new AddingNewEventHandler(bindingSource_AddingNew);

    // Bind to the DataGridView.

    dataGridView.DataSource = bindingSource;
}

private void bindingSource_AddingNew(object sender, AddingNewEventArgs e)
{
    // Use non-default constructor for the new object that will
    // be the source for the new row.

    e.NewObject = new CustomItem("Not default content");
}

An alternative is to use the DataGridView's DefaultValuesNeeded event, but the object has already been constructed by the time this event fires.

Inconsistent Connection Pooling Behavior

Jason Pease19-Dec-06 3:16

Jason Pease

19-Dec-06 3:16

I'm not sure if anyone will be able to help me with this problem without actually debugging the code, but I thought I'd give it a shot.

Here's the situation. I have a fairly mature and stable C#/ASP.NET application that I inherited a few years back. I'm familiar with nearly all of the code, but there are few classes here and there that I've never had to deal with; I know they work and that's it.

Late last night we came across a bug in which connections were getting leaked until the pool was saturated with the default 100 connections. It turned out that the connections were getting orphaned in a class that hasn't been touched in about five years. As strange as that is, the part that I really can't explain is that the method is called an several places in the application and it works correctly. However, when it is called in a page that was recently added to the application it leaks connections like a siv.

If it can help, here's the offending method (underscores added for legibility).

<br />
public int GetUserID(String UserName) <br />
{<br />
________// Create Instance of Connection and Command Object<br />
________SqlConnection myConnection = new SqlConnection(ConfigurationSettings.AppSettings["connectionStringUSR"]);<br />
________SqlCommand myCommand = new SqlCommand("GetSingleUserID", myConnection);<br />
<br />
________// Mark the Command as a SPROC<br />
________myCommand.CommandType = CommandType.StoredProcedure;<br />
<br />
________// Add Parameters to SPROC<br />
________SqlParameter parameterEmail = new SqlParameter("@Email", SqlDbType.NVarChar, 100);<br />
________parameterEmail.Value = UserName;<br />
________myCommand.Parameters.Add(parameterEmail);<br />
<br />
<br />
________if ((parameterEmail.Value != null) && (parameterEmail.Value != System.DBNull.Value)) <br />
________{<br />
________________// Open the database connection and execute the command<br />
________________myConnection.Open();<br />
<br />
________________SqlDataReader dr = myCommand.ExecuteReader(CommandBehavior.CloseConnection);<br />
________________if(dr.Read()==true)<br />
________________{<br />
________________________if(dr.IsDBNull(0))<br />
________________________________return -1;<br />
________________________else<br />
________________________________return dr.GetInt32(0);<br />
________________}<br />
________________else<br />
________________{<br />
________________________return -1;<br />
________________}<br />
________}<br />
________else<br />
________{<br />
________________return -1;<br />
________}<br />
}<br />
<br />

The myConnection.Close() is missing, but the CommandBehavior is set to CloseConnection so it should be getting closed correctly.

I am at a complete loss why this code would behave different based on what on what's below it on the stack, what in the session, or what's in some static variable, but that seems to be the case.

If anyone can help me figure this out I'll owe you dinner.

Thanks, Jason

althamda19-Dec-06 3:23

althamda

19-Dec-06 3:23

I don't know about you but I don't really trust something to close my connections for me. I'd have the open in a try block and the close in a finally block.

Jason Pease19-Dec-06 3:32

Jason Pease

19-Dec-06 3:32

I couldn't agree more, in fact that's precisely what I did to correct the problem. But I also need to explain why the previous code behaved as it did, both for formal justifications as well as my own curiosity.

althamda19-Dec-06 3:45

althamda

19-Dec-06 3:45

I'd say that a connection that is opened must always be closed, no exceptions. It's plain bad coding to rely on something else to auto close a connection.

As for why the code behaved as it did - I'd just put it down to badly written code.