C# express addition DataRow related warning

[michael_geller]

While experimenting with binding datasets to an MS DataGridView, I get
a warning that tells me that my DataRows are "either undeclared or was
never assigned". Assuming that I am reading the documentation
correctly, you are supposed to create a DataRow using the
"DataTable.NewR ow()" method. This is what I do in my app. As a matter
of fact, the DataRow constructor appears to be protected so I can't
directly create it if I want to. Is this warning a bug in MS C#
express? Or am I doing something wrong? If I ignore the warning and
run the app, it works as expected. Just trying to sort out the best
way to remove this warning.

-Michael

[Nicholas Paldino [.NET/C# MVP]]

Michael,

Can you post the code? This error has little to do with the actual way
you create the data row, but rather, a variable that is not assigned
properly.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard. caspershouse.co m

"mi************ @hotmail.com" <ge******@gmail .com> wrote in message
news:11******** **************@ g14g2000cwa.goo glegroups.com.. .

While experimenting with binding datasets to an MS DataGridView, I get
a warning that tells me that my DataRows are "either undeclared or was
never assigned". Assuming that I am reading the documentation
correctly, you are supposed to create a DataRow using the
"DataTable.NewR ow()" method. This is what I do in my app. As a matter
of fact, the DataRow constructor appears to be protected so I can't
directly create it if I want to. Is this warning a bug in MS C#
express? Or am I doing something wrong? If I ignore the warning and
run the app, it works as expected. Just trying to sort out the best
way to remove this warning.

-Michael

[MuZZy]

mi************@ hotmail.com wrote:

While experimenting with binding datasets to an MS DataGridView, I get
a warning that tells me that my DataRows are "either undeclared or was
never assigned". Assuming that I am reading the documentation
correctly, you are supposed to create a DataRow using the
"DataTable.NewR ow()" method. This is what I do in my app. As a matter
of fact, the DataRow constructor appears to be protected so I can't
directly create it if I want to. Is this warning a bug in MS C#
express? Or am I doing something wrong? If I ignore the warning and
run the app, it works as expected. Just trying to sort out the best
way to remove this warning.

-Michael

You create a row by doing:

DataRow dr = dtDataTable.New Row();

Nut after that you need to add that row to the table:

dtDataTable.Row s.Add(dr);

....because beleive it or not, the row created by NewRow doesn't belong to the table by default.

Hope it helps,
MuZZy

[michael_geller]

Here is the code. I know that it isn't good practice to put data
related code directly together with GUI code. This was just a simple
test to familiarize myself with the MS data related classes; search for
the string "DataRow dr = d.NewRow();" to jump to relavent section of
the code; I think I'm doing things by the book as per MS documentation,
but perhaps I'm missing something such that I'm getting the warning in
C# Express Edition; note that the code compiles and runs fine...
----------------------------------------------

using System.Data;

namespace Test
{
partial class Form1
{
/// <summary>
/// Required designer variable.
/// </summary>
private System.Componen tModel.IContain er components = null;

/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing ">true if managed resources should be
disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Disp ose();
}
base.Dispose(di sposing);
}

#region Windows Form Designer generated code

/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeCompo nent()
{
this.d = new System.Data.Dat aTable();
this.ds = new System.Data.Dat aSet();
this.dataGridVi ew1 = new
System.Windows. Forms.DataGridV iew();
this.button1 = new System.Windows. Forms.Button();
this.clientIDDa taGridViewTextB oxColumn = new
System.Windows. Forms.DataGridV iewTextBoxColum n();
this.clientName DataGridViewTex tBoxColumn = new
System.Windows. Forms.DataGridV iewTextBoxColum n();

((System.Compon entModel.ISuppo rtInitialize)(t his.d)).BeginIn it();

((System.Compon entModel.ISuppo rtInitialize)(t his.ds)).BeginI nit();

((System.Compon entModel.ISuppo rtInitialize)(t his.dataGridVie w1)).BeginInit( );
this.SuspendLay out();
//
// d
//
this.d.TableNam e = "Client";
//
// ds
//
this.ds.DataSet Name = "ClientDB";
this.ds.Tables. AddRange(new System.Data.Dat aTable[] {
this.d});

d.Columns.Add(" ClientID",
System.Type.Get Type("System.In t32"));
d.Columns.Add(" ClientName",
System.Type.Get Type("System.St ring"));

DataRow dr = d.NewRow();
dr["ClientID"] = 2;
dr["ClientName "] = "Fidelity";
d.Rows.Add(dr);

//
// dataGridView1
//
this.dataGridVi ew1.AllowUserTo OrderColumns = true;
this.dataGridVi ew1.AutoGenerat eColumns = false;
this.dataGridVi ew1.ColumnHeade rsHeightSizeMod e =
System.Windows. Forms.DataGridV iewColumnHeader sHeightSizeMode .AutoSize;
this.dataGridVi ew1.Columns.Add Range(new
System.Windows. Forms.DataGridV iewColumn[] {
this.clientIDDa taGridViewTextB oxColumn,
this.clientName DataGridViewTex tBoxColumn});
this.dataGridVi ew1.DataMember = "Client";
this.dataGridVi ew1.DataSource = this.ds;
this.dataGridVi ew1.Location = new System.Drawing. Point(139,
69);
this.dataGridVi ew1.Name = "dataGridView1" ;
this.dataGridVi ew1.Size = new System.Drawing. Size(240,
150);
this.dataGridVi ew1.TabIndex = 0;
//
// button1
//
this.button1.Lo cation = new System.Drawing. Point(457, 71);
this.button1.Na me = "button1";
this.button1.Si ze = new System.Drawing. Size(154, 72);
this.button1.Ta bIndex = 1;
this.button1.Te xt = "button1";
this.button1.Us eVisualStyleBac kColor = true;
this.button1.Cl ick += new
System.EventHan dler(this.butto n1_Click);
//
// clientIDDataGri dViewTextBoxCol umn
//
this.clientIDDa taGridViewTextB oxColumn.DataPr opertyName =
"ClientID";
this.clientIDDa taGridViewTextB oxColumn.Header Text =
"ClientID";
this.clientIDDa taGridViewTextB oxColumn.Name =
"clientIDDataGr idViewTextBoxCo lumn";
//
// clientNameDataG ridViewTextBoxC olumn
//
this.clientName DataGridViewTex tBoxColumn.Data PropertyName =
"ClientName ";
this.clientName DataGridViewTex tBoxColumn.Head erText =
"ClientName ";
this.clientName DataGridViewTex tBoxColumn.Name =
"clientNameData GridViewTextBox Column";
//
// Form1
//
this.AutoScaleD imensions = new System.Drawing. SizeF(6F,
13F);
this.AutoScaleM ode =
System.Windows. Forms.AutoScale Mode.Font;
this.ClientSize = new System.Drawing. Size(834, 663);
this.Controls.A dd(this.button1 );
this.Controls.A dd(this.dataGri dView1);
this.Name = "Form1";
this.Text = "Form1";

((System.Compon entModel.ISuppo rtInitialize)(t his.d)).EndInit ();

((System.Compon entModel.ISuppo rtInitialize)(t his.ds)).EndIni t();

((System.Compon entModel.ISuppo rtInitialize)(t his.dataGridVie w1)).EndInit();
this.ResumeLayo ut(false);

}

#endregion

private System.Windows. Forms.DataGridV iew dataGridView1;
private System.Windows. Forms.Button button1;
private System.Data.Dat aTable d;
private System.Data.Dat aSet ds;
private System.Windows. Forms.DataGridV iewTextBoxColum n
clientIDDataGri dViewTextBoxCol umn;
private System.Windows. Forms.DataGridV iewTextBoxColum n
clientNameDataG ridViewTextBoxC olumn;
}
}