My Ado.Net code is on a Public Holiday
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Good Afternoon All As you know in South Africa today is a Election day, i think my ado.net code went to the Elections tooo i have this code in my DAL
public DataSet Lis_Databases(String DB)
{Strcon = GetConnectionString(DB); con = new SqlConnection(Strcon); cmdselect = new SqlCommand(); cmdselect.CommandText = "\[dbo\].\[sp\_ListDatabasesOfType\_Booking\]"; cmdselect.CommandType = CommandType.StoredProcedure; cmdselect.Connection = con; da = new SqlDataAdapter(); da.SelectCommand = cmdselect; DataSet ds = new DataSet(); try { con.Open(); da.Fill(ds); } catch (SqlException) { throw; } finally { if (con != null) { con.Close(); } } return ds; }and i call this code in my BLL like this
public DataSet Lis_Databases(String DB)
{
DAL.DAL obj = new DAL.DAL();DataSet ds = new DataSet(); try { ds = obj.Lis\_Databases(DB); } catch (SqlException) { throw; } finally { obj = null; } return ds; }And call use it like this in my PL(Presention Layer)
private void List_Databases_Grid()
{BLL.BLL obj = new BLL.BLL(); DataSet ds = new DataSet(); try { ds = obj.Lis\_Databases(Convert.ToString(Session\["ActiveDatabase"\])); if (ds.Tables\[0\].Rows.Count > 0) { GridView\_Database\_list.DataSource = ds; GridView\_Database\_list.DataBind(); } else { lblMessage.Text = "No Booking Database Avaiable,Create one"; lblMessage.Visible = true; lblMessage.ForeColor = System.Drawing.Color.Red; } } catch (SqlException ex) { lblMessage.Visible = true; lblMessage.Text = "The List cannot be Binded, Please Contact ITS" + ex.Message; lblMessage.ForeColVuyiswa Maseko wrote:
if (ds.Tables[0].Rows.Count > 0){change that code to
if (ds.Tables.Count > 0 && ds.Tables[0].Rows.Count > 0){hope it helpsdhaim ing ngarso sung tulodho, ing madyo mangun karso, tut wuri handayani. "Ki Hajar Dewantoro" in the front line gave a lead, in the middle line build goodwill, in the behind give power support
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Vuyiswa Maseko wrote:
if (ds.Tables[0].Rows.Count > 0){change that code to
if (ds.Tables.Count > 0 && ds.Tables[0].Rows.Count > 0){hope it helpsdhaim ing ngarso sung tulodho, ing madyo mangun karso, tut wuri handayani. "Ki Hajar Dewantoro" in the front line gave a lead, in the middle line build goodwill, in the behind give power support
Good Day Mbah Dhaim I have added such a Code to Check if there any rows and your code will check if there any tables in the dataset. but my Problem is here
GridView_Database_list.DataSource = ds;
i get
Object reference not set to an instance of an object.
Error Thank you
Vuyiswa Maseko, Few companies that installed computers to reduce the employment of clerks have realized their expectations.... They now need more and more expensive clerks even though they call them "Developers" or "Programmers." C#/VB.NET/ASP.NET/SQL7/2000/2005/2008 http://www.vuyiswamaseko.tiyaneProperties.co.za vuyiswa@its.co.za http://www.itsabacus.co.za/itsabacus/
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Good Day Mbah Dhaim I have added such a Code to Check if there any rows and your code will check if there any tables in the dataset. but my Problem is here
GridView_Database_list.DataSource = ds;
i get
Object reference not set to an instance of an object.
Error Thank you
Vuyiswa Maseko, Few companies that installed computers to reduce the employment of clerks have realized their expectations.... They now need more and more expensive clerks even though they call them "Developers" or "Programmers." C#/VB.NET/ASP.NET/SQL7/2000/2005/2008 http://www.vuyiswamaseko.tiyaneProperties.co.za vuyiswa@its.co.za http://www.itsabacus.co.za/itsabacus/
OK, which object is it failing on, the gridview or the dataset? (I don't see how it could possibly fail on the dataset though). Is the Gridview actually in your controls collection? Do you add it dynamically (in which case, before you add it do you actually instantiate it properly?) or is it a control in your aspx page? And if so, if you're using frames are you not trying to access a control that is in a different frame? Or maybe the gridview is in a content holder of and you're trying to access it from a master page?
var question = (_2b || !(_2b));
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Good Day Mbah Dhaim I have added such a Code to Check if there any rows and your code will check if there any tables in the dataset. but my Problem is here
GridView_Database_list.DataSource = ds;
i get
Object reference not set to an instance of an object.
Error Thank you
Vuyiswa Maseko, Few companies that installed computers to reduce the employment of clerks have realized their expectations.... They now need more and more expensive clerks even though they call them "Developers" or "Programmers." C#/VB.NET/ASP.NET/SQL7/2000/2005/2008 http://www.vuyiswamaseko.tiyaneProperties.co.za vuyiswa@its.co.za http://www.itsabacus.co.za/itsabacus/
According to your logic,
dscan't be empty. I guess that you already added a watch to verify that. Let's break the statement that the compiler is complaining about into some smaller parts;GridView_Database_list.DataSource = ds;
Could it be that "GridView_Database_list" is null? Assigning a null-value to a variable isn't likely to cause errors, but assigning a value to something that is null, probably will. --edit-- Read Greg's post - he's right in noticing that there may be some action triggered from the Grid itself once there is an assignment to the DataSource property :)
I are troll :)
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Good Day Mbah Dhaim I have added such a Code to Check if there any rows and your code will check if there any tables in the dataset. but my Problem is here
GridView_Database_list.DataSource = ds;
i get
Object reference not set to an instance of an object.
Error Thank you
Vuyiswa Maseko, Few companies that installed computers to reduce the employment of clerks have realized their expectations.... They now need more and more expensive clerks even though they call them "Developers" or "Programmers." C#/VB.NET/ASP.NET/SQL7/2000/2005/2008 http://www.vuyiswamaseko.tiyaneProperties.co.za vuyiswa@its.co.za http://www.itsabacus.co.za/itsabacus/
DataSet is referenced type, as you see in your BLL and PL in finally part you destroy your object (DAL and BLL) :
finally {obj = null}, your dataset in PL will be lost reference too. remove finally part of your code. hope it helpsdhaim ing ngarso sung tulodho, ing madyo mangun karso, tut wuri handayani. "Ki Hajar Dewantoro" in the front line gave a lead, in the middle line build goodwill, in the behind give power support
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According to your logic,
dscan't be empty. I guess that you already added a watch to verify that. Let's break the statement that the compiler is complaining about into some smaller parts;GridView_Database_list.DataSource = ds;
Could it be that "GridView_Database_list" is null? Assigning a null-value to a variable isn't likely to cause errors, but assigning a value to something that is null, probably will. --edit-- Read Greg's post - he's right in noticing that there may be some action triggered from the Grid itself once there is an assignment to the DataSource property :)
I are troll :)
Thanks for your Reply The Gridview is Clean , there is nothing Assign to it.
Vuyiswa Maseko, Few companies that installed computers to reduce the employment of clerks have realized their expectations.... They now need more and more expensive clerks even though they call them "Developers" or "Programmers." C#/VB.NET/ASP.NET/SQL7/2000/2005/2008 http://www.vuyiswamaseko.tiyaneProperties.co.za vuyiswa@its.co.za http://www.itsabacus.co.za/itsabacus/
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OK, which object is it failing on, the gridview or the dataset? (I don't see how it could possibly fail on the dataset though). Is the Gridview actually in your controls collection? Do you add it dynamically (in which case, before you add it do you actually instantiate it properly?) or is it a control in your aspx page? And if so, if you're using frames are you not trying to access a control that is in a different frame? Or maybe the gridview is in a content holder of and you're trying to access it from a master page?
var question = (_2b || !(_2b));
Thank you Greg The GridView was inside the UpdateProgress Control :rolleyes: My Mistake, Thank you.
Vuyiswa Maseko, Few companies that installed computers to reduce the employment of clerks have realized their expectations.... They now need more and more expensive clerks even though they call them "Developers" or "Programmers." C#/VB.NET/ASP.NET/SQL7/2000/2005/2008 http://www.vuyiswamaseko.tiyaneProperties.co.za vuyiswa@its.co.za http://www.itsabacus.co.za/itsabacus/
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DataSet is referenced type, as you see in your BLL and PL in finally part you destroy your object (DAL and BLL) :
finally {obj = null}, your dataset in PL will be lost reference too. remove finally part of your code. hope it helpsdhaim ing ngarso sung tulodho, ing madyo mangun karso, tut wuri handayani. "Ki Hajar Dewantoro" in the front line gave a lead, in the middle line build goodwill, in the behind give power support
No No the Finally Part will only Destroy the object not the Dataset, the Dataset will be Teturned Correctly. Thank you for your help i have the problem The GridView was inside the UpdateProgress Control :rolleyes: My Mistake, Thank you.
Vuyiswa Maseko, Few companies that installed computers to reduce the employment of clerks have realized their expectations.... They now need more and more expensive clerks even though they call them "Developers" or "Programmers." C#/VB.NET/ASP.NET/SQL7/2000/2005/2008 http://www.vuyiswamaseko.tiyaneProperties.co.za vuyiswa@its.co.za http://www.itsabacus.co.za/itsabacus/
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No No the Finally Part will only Destroy the object not the Dataset, the Dataset will be Teturned Correctly. Thank you for your help i have the problem The GridView was inside the UpdateProgress Control :rolleyes: My Mistake, Thank you.
Vuyiswa Maseko, Few companies that installed computers to reduce the employment of clerks have realized their expectations.... They now need more and more expensive clerks even though they call them "Developers" or "Programmers." C#/VB.NET/ASP.NET/SQL7/2000/2005/2008 http://www.vuyiswamaseko.tiyaneProperties.co.za vuyiswa@its.co.za http://www.itsabacus.co.za/itsabacus/
Vuyiswa Maseko wrote:
My Mistake, Thank you.
you're welcome this day i learn that referenced type will not destroy although its parent destroyed. thank you very much.
dhaim ing ngarso sung tulodho, ing madyo mangun karso, tut wuri handayani. "Ki Hajar Dewantoro" in the front line gave a lead, in the middle line build goodwill, in the behind give power support
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Vuyiswa Maseko wrote:
My Mistake, Thank you.
you're welcome this day i learn that referenced type will not destroy although its parent destroyed. thank you very much.
dhaim ing ngarso sung tulodho, ing madyo mangun karso, tut wuri handayani. "Ki Hajar Dewantoro" in the front line gave a lead, in the middle line build goodwill, in the behind give power support
You are Welcome :)
Vuyiswa Maseko, Few companies that installed computers to reduce the employment of clerks have realized their expectations.... They now need more and more expensive clerks even though they call them "Developers" or "Programmers." C#/VB.NET/ASP.NET/SQL7/2000/2005/2008 http://www.vuyiswamaseko.tiyaneProperties.co.za vuyiswa@its.co.za http://www.itsabacus.co.za/itsabacus/