error for new row and data sql

Gerhard van der Merwe

Please help

I keep getting the following error: "Object reference not set to an instance of an object." for the code DataRow myRow = myTable.NewRow();

string connectionString = @"data source = GERHARDVDM28-PC; initial catalog = RacerUI; integrated security=SSPI";

string commandString = @"SELECT * FROM Entries";

SqlDataAdapter dataAdapter = new SqlDataAdapter(commandString, connectionString);

SqlCommandBuilder scb = new SqlCommandBuilder(dataAdapter);

DataSet racerUIDataSet = new DataSet();

DataTable myTable = racerUIDataSet.Tables["Entries"];

this.entriesTableAdapter.Fill(this.racerUIDataSet.Entries);

DataRow myRow = myTable.NewRow();

myRow[0] = RacerName;

myRow[1] = BikeManufacturer;

myRow[2] = RaceNumber;

myRow[3] = Team;

myTable.Rows.Add(myRow);

dataAdapter.Update(racerUIDataSet, "Entries");

racerUIDataSet.AcceptChanges();

4 Replies

Know the answer? Post it — somebody with the same question will find it here.

try..

Decimal Value = (RaceNumber.Text.ToString().Trim() == "" ? 0 : Convert.ToDecimal(this.RaceNumber.Text));

Gerhard van der Merwe15y ago

public void RaceNumber_TextChanged(object sender, EventArgs e)
{
Decimal Value = int.Parse(RaceNumber.Text);
if (this.RaceNumber.Text == "" || this.RaceNumber.Text == null)
Value = 0;
else
Value = Convert.ToDecimal(this.RaceNumber.Text);

}
Gerhard van der Merwe15y ago
Hi, managed to sort out the null values, thanks.
I am now able to add data to the Table but when I get to one specific textbox with numeric input I get the following error when compiling:
Unable to cast object of type 'System.Windows.Forms.TextBox' to type 'System.IConvertible'.Couldn't store in RaceNumber Column. Expected type is Decimal.