convertion failed

I assume from the error message that investor_cnic is an int column in the database table.

However, even if you remove the hyphens from 34101-1212121-1, you still won't be able to convert it to the int type as the latter can't exceed 10 digits. It will be automatically converted to the decimal type instead.

So, if you do in fact want to insert this value into the database (and not just a part of it), you'll need to change the column type to bigint, decimal or varchar first.

It will be helpful if you debug the code and find the exception Line.

Try with also below modification:
1.Change Datatype of investor_cnic by nvarchar(SIZE).
2.Despite of
dataGridView1.Rows.RemoveAt(dataGridView1.SelectedRows[0].Index);
line

Re-Bind your gridview.

hi,

I think there is no need to put single quote before and after the parameter name...
try...
delcmd.CommandText = "DELETE FROM add_investor WHERE investor_cnic=@Investor";

hope this will help you...

no that is not reason of error.  error is due to -- singns i mdi fied the code but now it delets data from datagridvie but not from database can you help see the code



SqlCommand delcmd = new SqlCommand();
                        delcmd.CommandText = "DELETE FROM add_investor WHERE investor_cnic='@Investor'";
                        delcmd.Parameters.Add("@Investor", System.Data.SqlDbType.NChar);
                        delcmd.Parameters["@Investor"].Value = dataGridView1.SelectedRows[0].Cells[0].Value.ToString();
                        my.Open();
                        delcmd.Connection = my;

                        delcmd.ExecuteNonQuery();
                        my.Close();
                        dataGridView1.Rows.RemoveAt(dataGridView1.SelectedRows[0].Index);
                        my.Close();

hi,

it might be possible investor_cnic is int field and dataGridView1.SelectedRows[0].Cells[0].Value.ToString()  return string value like '34101-1212121-1' , so this error occurred....
 
so check whether correct data you are pass in where condition..

hope this will help you.