Remove column which has expression set

Farhan Shariff

I want to remove a column from datatable

the column is a part of expression I want to remove it once the expression is calculated.

Lower.Expression = "(Convert(µ,'System.Double')-Convert(LSL,'System.Double'))/(3.0*sigma)";
Upper.Expression = "(Convert(USL,'System.Double')-Convert(µ,'System.Double'))/(3.0*sigma)";
CpK.Expression = "IIF(Lower < Upper, Lower, Upper)";

I want to remove lower and upper once the data is populated

2 Replies

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Vulpes12y ago
Well, first of all, you can't remove columns from a DataTable if they are involved in an Expression property. If you try to do so, you'll get an exception.

If you really need to do this, then you'd have to forego setting the Expression property and simply calculate the values of the 'computed' column manually before removing the 'surplus' columns.

Secondly, you can't hide columns in a DataTable because the DataColumn class doesn't have a Visible property - hence the exception you're getting. What you could do is to bind the table to (say) a DataGridView and then hide the appropriate columns of that.
Farhan Shariff12y ago
I tried to hide it table1.Columns["Lower"].Visible = false; It say you are missing directive or an assemble reference ?