add data in datagrid

[riska]

Hi,
I have a problem, please help me to solve it.
I want to make a column in a datagrid and that column get data from two column beside. For example i want make a column that get data from amount two column beside. That data will display when I insert new row. I use a datatable in my datagrid.

When i add new row, there will be error.

[cafedreamz]

It would be better for you to do all calculations in the SQL query itself before you attach the result to the datagrid.So if u want to do some calculations on one column and show it in another column,it will be easy for you if do it in the query itself.Hope this helps.

[jhammer]

Add a DataColumn to the table. Set a name to it, and then set the Expression proeprty of it to be "columnA * columnB" where those are the names of the two columns. You can see an example in MSDN:

private void CalcColumns(){
    DataColumn cPrice;
    DataColumn cTax;
    DataColumn cTotal;
    DataTable myTable = new DataTable ();
 
    // Create the first column.
    cPrice = new DataColumn();
    cPrice.DataType = System.Type.GetType("System.Decimal");
    cPrice.ColumnName = "price";
    cPrice.DefaultValue = 50;
         
    // Create the second, calculated, column.
    cTax = new DataColumn();
    cTax.DataType = System.Type.GetType("System.Decimal");
    cTax.ColumnName = "tax";
    cTax.Expression = "price * 0.0862";
         
    // Create third column.
    cTotal = new DataColumn();
    cTotal.DataType = System.Type.GetType("System.Decimal");
    cTotal.ColumnName = "total";
    cTotal.Expression = "price + tax";
    
    // Add columns to DataTable.
    myTable.Columns.Add(cPrice);
    myTable.Columns.Add(cTax);
    myTable.Columns.Add(cTotal);
    DataRow myRow;
    myRow = myTable.NewRow();
    myTable.Rows.Add(myRow);
    DataView myView = new DataView(myTable);
    dataGrid1.DataSource = myView;
 }

remember to remove the column before you update to database.