How I can search rows in a datatable with a searchstring?

Question

I want to search rows in my DataTable.

I\'ve tried this:

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Answer 1

You get the error because the parameter to Select is the filterExpression and you have passed all columns. Understand the filterExpression as a WHERE clause in sql. You want all columns but you want to filter by just one. You get all columns anyway since they are all part of the DataTable/DataView so you don't need to list them explicitely.

You could either use the DataTable.Select, DatView.RowFilter methods or LINQ-to-DataSet:

LINQ-To-DataSet (which i prefer):

var filtered = tb.AsEnumerable()
    .Where(r => r.Field("CREATOR").Contains(searchstring));

ADO.NET(DataTable.Select):

DataRow[] filteredRows = tb.Select("CREATOR LIKE '%" + searchstring + "%'");

ADO.NET(DataView.RowFilter):

 tb.DefaultView.RowFilter = "CREATOR LIKE '%" + searchstring + "%'";

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If you want to search for this string in any column instead:

DataRow[] filteredRows = tb.Select("FIRSTNAME LIKE '%" + searchstring + "%' OR LASTNAME LIKE '%" + searchstring + "%' OR NAME LIKE '%" + searchstring + "%' OR COMPANY LIKE '%" + searchstring + "%' OR CREATOR LIKE '%" + searchstring + "%'");

The same with Linq:

var filtered = tb.AsEnumerable()
    .Where(r => r.Field("FIRSTNAME").Contains(searchstring)
           ||   r.Field("LASTNAME").Contains(searchstring))
           ||   r.Field("NAME").Contains(searchstring)
           ||   r.Field("COMPANY").Contains(searchstring)
           ||   r.Field("CREATOR").Contains(searchstring));