I'm still relatively new to LINQ, and have done more stumbling around than anything, but I have really liked what I have seen so far. So with that in mind, I have a VB.NET search routine, part of which is provided, below, that checks all Text cells in a DataGridView for a given string (inclusive), using a basic set of nested loops to perform the search:
' Search for the first occurrence of the given string
For Each row As DataGridViewRow In dgvMembers.Rows
' Skip the new row
If row.IsNewRow Then Exit For
' Loop through all the cells in the current row
For Each cell As DataGridViewCell In row.Cells
' Skip non-text cells
If cell.GetType IsNot GetType(DataGridViewTextBoxCell) Then Continue For
' Search for our matching text
If cell.Value.ToString.ToUpper.Contains(searchText) Then
' Select the cell if we have a match
dgvMembers.CurrentCell = cell
WriteMessage("String '{0}' found.", searchText)
Exit Sub
End If
Next
Next
' If we get to this point, we didn't find anything
WriteMessage("String '{0}' NOT found.", searchText)
Pretty straightforward. Now, my question is: is there a way to replicate this behavior using LINQ? Basically I would like the query to select (or return) the first DataGridViewCell whose text contains the search string. I've done some tinkering with sub-queries and the lik开发者_开发百科e, but I'm still having trouble wrapping my brain around the concepts (too many years of writing T-SQL, I guess).
Obviously the nested loop works fine, so this is more of a curiosity, really. Thanks in advance!
I was able to use this code with some success:
Dim qry = From theRow as DataGridViewRow In dgvMembers.Rows, _
theCell as DataGridViewCell In theRow.Cells _
Where theCell.Value.ToString.ToUpper = searchText _
Select theCell
Dim matchCell as DataGridViewCell = qry.First
dgvMembers.CurrentCell = matchCell
... etc...
Posting a full code snippet using knslyr's response, but in the context of my original code, just for posterity:
Try
' Search (case insensitive) for the first occurrence of the given string
Dim foundCell As DataGridViewCell = (
From row As DataGridViewRow In dgvMembers.Rows,
cell As DataGridViewCell In row.Cells
Where cell.Value.ToString.ToUpper.Contains(searchText)
Select cell
).First
' If we have a match, select it
If foundCell IsNot Nothing Then
' Select the cell if we have a match
dgvMembers.CurrentCell = foundCell
WriteMessage("String '{0}' found.", searchText)
Else
' No cell found. Whoops.
WriteMessage("String '{0}' NOT found.", searchText)
End If
Catch ex As Exception
' An exception probably means the New row was reached. So, no dice.
WriteMessage("String '{0}' NOT found.", searchText)
End Try
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