Cannot cast DBNull.Value to type 'System.DateTime', Please use nullable types

Question

getting error while date is null . error line- DateTime renewalDate = row.Field("RenewalDate");

protected void GrdV_Projects_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow )
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
        DataRow row = ((DataRowView)e.Row.DataItem).Row;
        DateTime renewalDate = row.Field<DateTime>("RenewalDate");
        if (renewalDate.Date > DateTime.Today)
            e.Row.Cells[7].BackColor = System.Drawing.ColorTranslator.FromHtml("#669B1F");
        else
            e.Row.Cells[7].BackColor = System.Drawing.ColorTranslator.FromHtml("#FF8234");
        }
    }
}

Solution 1

you cant convert null to date, make date-time nullable

 DateTime? renewalDate = row.Field<DateTime?>("RenewalDate")

also in your if statement

 if (renewalDate.HasValue && renewalDate.Value.Date > DateTime.Today)

Solution 2

The error is pretty clear I think. You can't assign a NULL value to a DateTime. You have two options:

1. Make the field NOT NULL in the DB to ensure it cannot return NULL.

2. Use a DateTime? instead of DateTime:

   DateTime? renewalDate = row.Field<DateTime?>("RenewalDate");

Comments

[krishna mohan]

Error 25 'System.Nullable<System.DateTime>' does not contain a definition for 'Date' and no extension method 'Date' accepting a first argument of type 'System.Nullable<System.DateTime>' could be found (are you missing a using directive or an assembly referenence@sanu

[Hans Kesting]

@krishnamohan - you can use renewalDate.Value.Date, but first check renewalDate.HasValue to see if you really have a value.

[krishna mohan]

i cannot use var . im using 3.5 framework@user5114524

[krishna mohan]

DateTime? renewalDate = row.Field<DateTime?>("RenewalDate"); if (renewalDate > DateTime.Today) e.Row.Cells[7].BackColor = System.Drawing.ColorTranslator.FromHtml("#669B1F"); else is it correct?

[user5114524]

you need to consider null value in your if stmt

[user5114524]

change if : if (renewalDate.HasValue && renewalDate.Value.Date > DateTime.Today)