DATA GRID CALCULATION

Question

Please tell me how to perform calculations in Data Grid . Means adding 2 cells value in third cell of data Grid.
I am trying but its not working . It is showing error:
Object cannot be cast from DBNull to other types.
IF ANY ONE KNOWS THEN PLEASE SEND ME A COMPLETE CODE FOR CALCULATION IN DATA GRID.

Suthish Nair · Answer

duplicate post! http://www.c-sharpcorner.com/Forums/Thread/118311/calculation-in-data-grid.aspx

Vulpes · Answer

This code is for the Windows Form's DataGridView but you should be able to adapt it to other DataGrids.
The columns are assumed to be called "First", "Second" and "Sum". The grid is called dataGridView1.
If either First or Second is null or DBNull, then the calculation is meaningless and so nothing is written to the Sum column. Alternatively, you could substitute 0 for null values and do the calculation on that basis instead.
foreach (DataGridViewRow row in dataGridView1.Rows)             {                 double sum = 0.0, temp = 0.0;                 object value1 = row.Cells["First"].Value;                 object value2 = row.Cells["Second"].Value;
if (value1 != null && value1 != DBNull.Value)                 {                     double.TryParse(value1.ToString(), out sum); // uses 0 if cell contents can't be parsed to a double                 }                 else                 {                     continue; // don't bother with calculation                 }
if (value2 != null && value2 != DBNull.Value)                 {                     double.TryParse(value2.ToString(), out temp);                     sum += temp;                 }                 else                 {                     continue;                 }
row.Cells["Sum"].Value = sum; // or sum.ToString() if preferred             }