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How to Add *AND* Process Checkbox Column in a DataGridView?I'd like to find out the best way to add a cb column to a dgv and process efficiently. I see at least two ways of doing it. ------------------------------- 1) Add a cb to the dgv, iterate thru the dgv and update the bound fields if the cb has been checked. Then do the update and accept changes. How do I access the cb and its checked status? How to iterate thru dgv? Dim cbSelCol As New DataGridViewCheckBoxColumn dgv1.Columns.Insert(0, cbSelCol) With cbSelCol .HeaderText = "Select" .Name = "RecSel" .DisplayIndex = 0 .Frozen = True End With For Each dgv1????row in dgv1.rows if dgv1????row("RecSel").Checked then ...do some update process.... end if Try daEN.Update(dtEN) Catch ex As Exception 'An exception occurred End Try Next dtEN.AcceptChanges() ------------------------------- 2) Create an alias boolean field in the SELECT statement when creating the datatable. Then test the checkbox and update as applicable. How do I change the cell style to checkbox (of "RecSel")? How to test if checked? ENQrySel = "SELECT True as RecSel, ENDate, ... " "FROM ... WHERE ... ORDER BY ..." daEN.Fill(dtEN) dgv1.DataSource = dtEN DIM drEN as DataRow For Each drEN in dtEN.Rows If drEN("RecSel") ???Selected??? then ...do some update process.... End If Try daEN.Update(dtEN) Catch ex As Exception 'An exception occurred End Try Next dtEN.AcceptChanges() Which way is best/doable? Other suggestions? Thanks, Hexman I would choose #1. I assume you're binding the column to
a boolean field. Here's some info from Brian Noyes's book on databinding. I'm assuming you're not using ThreeState mode (allows True, False, and Indeterminate). The column with checkboxes in it contains cells of type DataGridViewCheckBoxCell. A value of Null or False will leave the checkbox unchecked. A value of true will check the box. The cell's value property can be set explicitly through programmatic code that accesses the cell in the Cells collection of the row, or it can be set through data binding. In another part of his code, he is going through the grid and checking the value of the checkbox for true/false like this: For Each row As DataGridViewRow In m_Grid.Rows Dim include As DataGridViewCheckBoxCell = _ TryCast(row.Cells("IncludeRate"), DataGridViewCheckBoxCell) If include IsNot Nothing AndAlso include.Value IsNot Nothing _ AndAlso (DirectCast(include.Value, Boolean)) = True Then 'Do something with the checkbox value; it's checked End If Next Hope this helps. Robin S. ---------------------------------------------- Show quoteHide quote "Hexman" <Hex***@binary.com> wrote in message news:n0hnn2hkisjd1hm4ps1dskisskb52n83sl@4ax.com... > Hello All, > > I'd like to find out the best way to add a cb column to a dgv and > process efficiently. I see at least two ways of doing it. > > ------------------------------- > 1) Add a cb to the dgv, iterate thru the dgv and update the bound > fields if the cb has been checked. Then do the update and accept > changes. How do I > access the cb and its checked status? How to iterate thru dgv? > > Dim cbSelCol As New DataGridViewCheckBoxColumn > > dgv1.Columns.Insert(0, cbSelCol) > With cbSelCol > .HeaderText = "Select" > .Name = "RecSel" > .DisplayIndex = 0 > .Frozen = True > End With > > For Each dgv1????row in dgv1.rows > if dgv1????row("RecSel").Checked then > ...do some update process.... > end if > Try > daEN.Update(dtEN) > Catch ex As Exception > 'An exception occurred > End Try > Next > dtEN.AcceptChanges() > > ------------------------------- > 2) Create an alias boolean field in the SELECT statement when creating > the datatable. Then test the checkbox and update as applicable. How > do I > change the cell style to checkbox (of "RecSel")? How to test if > checked? > > > ENQrySel = "SELECT True as RecSel, ENDate, ... " > "FROM ... WHERE ... ORDER BY ..." > daEN.Fill(dtEN) > dgv1.DataSource = dtEN > > DIM drEN as DataRow > For Each drEN in dtEN.Rows > If drEN("RecSel") ???Selected??? then > ...do some update process.... > End If > Try > daEN.Update(dtEN) > Catch ex As Exception > 'An exception occurred > End Try > Next > dtEN.AcceptChanges() > > > Which way is best/doable? Other suggestions? > > Thanks, > > Hexman > Yes Robin, it did help - I got the app running how I wanted it to work. I just have a question about the code you presented. I don't understand what
the "Dim include as...." statement is doing. Could you explain. My code that works now looks like this....and I didn't have to do any typecasting, etc. Am I going to regret the way I've done it later? Thanks also for the reference to Brian Noyes' book. I've got a lot of reading to do. Hexman --------------------------------------------------------------------- 'Add checkbox to dgv Dim cbSelCol As New DataGridViewCheckBoxColumn dgv1.Columns.Insert(0, cbSelCol) With cbSelCol .HeaderText = "Select" .Name = "RecSel" .DisplayIndex = 0 .Frozen = True End With 'Process each row in dgv For Each row As DataGridViewRow In dgv1.Rows If row.Cells("RecSel").Value = True Then ...do some update process.... End if Try daEN.Update(dtEN) Catch ex As Exception 'An exception occurred End Try Next dtEN.AcceptChanges() --------------------------------------------------------------------- Show quoteHide quote On Sun, 10 Dec 2006 11:31:43 -0800, "RobinS" <RobinS@NoSpam.yah.none> wrote: >I would choose #1. I assume you're binding the column to >a boolean field. > >Here's some info from Brian Noyes's book on databinding. >I'm assuming you're not using ThreeState mode (allows >True, False, and Indeterminate). > >The column with checkboxes in it contains cells of type >DataGridViewCheckBoxCell. > >A value of Null or False will leave the checkbox unchecked. >A value of true will check the box. > >The cell's value property can be set explicitly through >programmatic code that accesses the cell in the Cells >collection of the row, or it can be set through data binding. > >In another part of his code, he is going through the grid >and checking the value of the checkbox for true/false >like this: > >For Each row As DataGridViewRow In m_Grid.Rows > Dim include As DataGridViewCheckBoxCell = _ > TryCast(row.Cells("IncludeRate"), DataGridViewCheckBoxCell) > If include IsNot Nothing AndAlso include.Value IsNot Nothing _ > AndAlso (DirectCast(include.Value, Boolean)) = True Then > 'Do something with the checkbox value; it's checked > End If >Next > >Hope this helps. >Robin S. >---------------------------------------------- > >"Hexman" <Hex***@binary.com> wrote in message >news:n0hnn2hkisjd1hm4ps1dskisskb52n83sl@4ax.com... >> Hello All, >> >> I'd like to find out the best way to add a cb column to a dgv and >> process efficiently. I see at least two ways of doing it. >> >> ------------------------------- >> 1) Add a cb to the dgv, iterate thru the dgv and update the bound >> fields if the cb has been checked. Then do the update and accept >> changes. How do I >> access the cb and its checked status? How to iterate thru dgv? >> >> Dim cbSelCol As New DataGridViewCheckBoxColumn >> >> dgv1.Columns.Insert(0, cbSelCol) >> With cbSelCol >> .HeaderText = "Select" >> .Name = "RecSel" >> .DisplayIndex = 0 >> .Frozen = True >> End With >> >> For Each dgv1????row in dgv1.rows >> if dgv1????row("RecSel").Checked then >> ...do some update process.... >> end if >> Try >> daEN.Update(dtEN) >> Catch ex As Exception >> 'An exception occurred >> End Try >> Next >> dtEN.AcceptChanges() >> >> ------------------------------- >> 2) Create an alias boolean field in the SELECT statement when creating >> the datatable. Then test the checkbox and update as applicable. How >> do I >> change the cell style to checkbox (of "RecSel")? How to test if >> checked? >> >> >> ENQrySel = "SELECT True as RecSel, ENDate, ... " >> "FROM ... WHERE ... ORDER BY ..." >> daEN.Fill(dtEN) >> dgv1.DataSource = dtEN >> >> DIM drEN as DataRow >> For Each drEN in dtEN.Rows >> If drEN("RecSel") ???Selected??? then >> ...do some update process.... >> End If >> Try >> daEN.Update(dtEN) >> Catch ex As Exception >> 'An exception occurred >> End Try >> Next >> dtEN.AcceptChanges() >> >> >> Which way is best/doable? Other suggestions? >> >> Thanks, >> >> Hexman >> > This section is just a way to iterate through the rows
in the DataGridView and check the value of a checkbox. Dim include... casts the IncludeRate cell on that row as a DataGridViewCheckBoxCell. TryCast returns Nothing if it couldn't cast it as that type. So the next line checks to see if it's not nothing AndAlso the value is filled in AndAlso the value is a boolean and it's true, and if all of those conditions are true, then the checkbox is checked. >>For Each row As DataGridViewRow In m_Grid.Rows I think the way you have it is fine. My guess is that>> Dim include As DataGridViewCheckBoxCell = _ >> TryCast(row.Cells("IncludeRate"), DataGridViewCheckBoxCell) >> If include IsNot Nothing AndAlso include.Value IsNot Nothing _ >> AndAlso (DirectCast(include.Value, Boolean)) = True Then >> 'Do something with the checkbox value; it's checked >> End If >>Next Mr. Noyes was trying to be really type-safe. Theoretically, he should know if the column "IncludeRate" is a checkbox or not, but I guess technically someone else could change it in the DataGridView definitions. (Like if they changed it to a 1-character field that held Y/N.) If that happened, his code wouldn't break. His book is really good; he had a good DataGridView example where he shows several of the different column types. He does a lot of parent/child stuff, too, and talks about making custom controls bindable. One thing to note: The examples in the book are in C#. However, the downloadable code is available in both C# and VB. The bright side is that after working through it, I can now read C# a lot more proficiently. The other side is that it made the book a tad more challenging. Good luck. Robin S. ------------------------------------ Show quoteHide quote "Hexman" <Hex***@binary.com> wrote in message news:pe0pn25nncakgmgvhb3m1t7qdc1h95mk5e@4ax.com... > Yes Robin, it did help - I got the app running how I wanted it to > work. I just have a question about the code you presented. I don't > understand what > the "Dim include as...." statement is doing. Could you explain. > > My code that works now looks like this....and I didn't have to do any > typecasting, etc. Am I going to regret the way I've done it later? > Thanks also > for the reference to Brian Noyes' book. I've got a lot of reading to > do. > > Hexman > > --------------------------------------------------------------------- > 'Add checkbox to dgv > Dim cbSelCol As New DataGridViewCheckBoxColumn > > dgv1.Columns.Insert(0, cbSelCol) > With cbSelCol > .HeaderText = "Select" > .Name = "RecSel" > .DisplayIndex = 0 > .Frozen = True > End With > > 'Process each row in dgv > For Each row As DataGridViewRow In dgv1.Rows > If row.Cells("RecSel").Value = True Then > ...do some update process.... > End if > Try > daEN.Update(dtEN) > Catch ex As Exception > 'An exception occurred > End Try > Next > dtEN.AcceptChanges() > --------------------------------------------------------------------- > > On Sun, 10 Dec 2006 11:31:43 -0800, "RobinS" <RobinS@NoSpam.yah.none> > wrote: > >>I would choose #1. I assume you're binding the column to >>a boolean field. >> >>Here's some info from Brian Noyes's book on databinding. >>I'm assuming you're not using ThreeState mode (allows >>True, False, and Indeterminate). >> >>The column with checkboxes in it contains cells of type >>DataGridViewCheckBoxCell. >> >>A value of Null or False will leave the checkbox unchecked. >>A value of true will check the box. >> >>The cell's value property can be set explicitly through >>programmatic code that accesses the cell in the Cells >>collection of the row, or it can be set through data binding. >> >>In another part of his code, he is going through the grid >>and checking the value of the checkbox for true/false >>like this: >> >>For Each row As DataGridViewRow In m_Grid.Rows >> Dim include As DataGridViewCheckBoxCell = _ >> TryCast(row.Cells("IncludeRate"), DataGridViewCheckBoxCell) >> If include IsNot Nothing AndAlso include.Value IsNot Nothing _ >> AndAlso (DirectCast(include.Value, Boolean)) = True Then >> 'Do something with the checkbox value; it's checked >> End If >>Next >> >>Hope this helps. >>Robin S. >>---------------------------------------------- >> >>"Hexman" <Hex***@binary.com> wrote in message >>news:n0hnn2hkisjd1hm4ps1dskisskb52n83sl@4ax.com... >>> Hello All, >>> >>> I'd like to find out the best way to add a cb column to a dgv and >>> process efficiently. I see at least two ways of doing it. >>> >>> ------------------------------- >>> 1) Add a cb to the dgv, iterate thru the dgv and update the bound >>> fields if the cb has been checked. Then do the update and accept >>> changes. How do I >>> access the cb and its checked status? How to iterate thru dgv? >>> >>> Dim cbSelCol As New DataGridViewCheckBoxColumn >>> >>> dgv1.Columns.Insert(0, cbSelCol) >>> With cbSelCol >>> .HeaderText = "Select" >>> .Name = "RecSel" >>> .DisplayIndex = 0 >>> .Frozen = True >>> End With >>> >>> For Each dgv1????row in dgv1.rows >>> if dgv1????row("RecSel").Checked then >>> ...do some update process.... >>> end if >>> Try >>> daEN.Update(dtEN) >>> Catch ex As Exception >>> 'An exception occurred >>> End Try >>> Next >>> dtEN.AcceptChanges() >>> >>> ------------------------------- >>> 2) Create an alias boolean field in the SELECT statement when >>> creating >>> the datatable. Then test the checkbox and update as applicable. >>> How >>> do I >>> change the cell style to checkbox (of "RecSel")? How to test if >>> checked? >>> >>> >>> ENQrySel = "SELECT True as RecSel, ENDate, ... " >>> "FROM ... WHERE ... ORDER BY ..." >>> daEN.Fill(dtEN) >>> dgv1.DataSource = dtEN >>> >>> DIM drEN as DataRow >>> For Each drEN in dtEN.Rows >>> If drEN("RecSel") ???Selected??? then >>> ...do some update process.... >>> End If >>> Try >>> daEN.Update(dtEN) >>> Catch ex As Exception >>> 'An exception occurred >>> End Try >>> Next >>> dtEN.AcceptChanges() >>> >>> >>> Which way is best/doable? Other suggestions? >>> >>> Thanks, >>> >>> Hexman >>> >> Thanks,
Hexman Show quoteHide quote On Sun, 10 Dec 2006 15:30:21 -0800, "RobinS" <RobinS@NoSpam.yah.none> wrote: >This section is just a way to iterate through the rows >in the DataGridView and check the value of a checkbox. > >Dim include... casts the IncludeRate cell on that row >as a DataGridViewCheckBoxCell. TryCast returns Nothing >if it couldn't cast it as that type. So the next line >checks to see if it's not nothing AndAlso the value >is filled in AndAlso the value is a boolean and it's >true, and if all of those conditions are true, then the >checkbox is checked. > >>>For Each row As DataGridViewRow In m_Grid.Rows >>> Dim include As DataGridViewCheckBoxCell = _ >>> TryCast(row.Cells("IncludeRate"), DataGridViewCheckBoxCell) >>> If include IsNot Nothing AndAlso include.Value IsNot Nothing _ >>> AndAlso (DirectCast(include.Value, Boolean)) = True Then >>> 'Do something with the checkbox value; it's checked >>> End If >>>Next > >I think the way you have it is fine. My guess is that >Mr. Noyes was trying to be really type-safe. Theoretically, >he should know if the column "IncludeRate" is a checkbox or >not, but I guess technically someone else could change it >in the DataGridView definitions. (Like if they changed >it to a 1-character field that held Y/N.) If that happened, >his code wouldn't break. > >His book is really good; he had a good DataGridView example >where he shows several of the different column types. He >does a lot of parent/child stuff, too, and talks about >making custom controls bindable. > >One thing to note: The examples in the book are in C#. >However, the downloadable code is available in both C# >and VB. The bright side is that after working through it, >I can now read C# a lot more proficiently. The other side >is that it made the book a tad more challenging. > >Good luck. >Robin S. >------------------------------------ > >"Hexman" <Hex***@binary.com> wrote in message >news:pe0pn25nncakgmgvhb3m1t7qdc1h95mk5e@4ax.com... >> Yes Robin, it did help - I got the app running how I wanted it to >> work. I just have a question about the code you presented. I don't >> understand what >> the "Dim include as...." statement is doing. Could you explain. >> >> My code that works now looks like this....and I didn't have to do any >> typecasting, etc. Am I going to regret the way I've done it later? >> Thanks also >> for the reference to Brian Noyes' book. I've got a lot of reading to >> do. >> >> Hexman >> >> --------------------------------------------------------------------- >> 'Add checkbox to dgv >> Dim cbSelCol As New DataGridViewCheckBoxColumn >> >> dgv1.Columns.Insert(0, cbSelCol) >> With cbSelCol >> .HeaderText = "Select" >> .Name = "RecSel" >> .DisplayIndex = 0 >> .Frozen = True >> End With >> >> 'Process each row in dgv >> For Each row As DataGridViewRow In dgv1.Rows >> If row.Cells("RecSel").Value = True Then >> ...do some update process.... >> End if >> Try >> daEN.Update(dtEN) >> Catch ex As Exception >> 'An exception occurred >> End Try >> Next >> dtEN.AcceptChanges() >> --------------------------------------------------------------------- >> >> On Sun, 10 Dec 2006 11:31:43 -0800, "RobinS" <RobinS@NoSpam.yah.none> >> wrote: >> >>>I would choose #1. I assume you're binding the column to >>>a boolean field. >>> >>>Here's some info from Brian Noyes's book on databinding. >>>I'm assuming you're not using ThreeState mode (allows >>>True, False, and Indeterminate). >>> >>>The column with checkboxes in it contains cells of type >>>DataGridViewCheckBoxCell. >>> >>>A value of Null or False will leave the checkbox unchecked. >>>A value of true will check the box. >>> >>>The cell's value property can be set explicitly through >>>programmatic code that accesses the cell in the Cells >>>collection of the row, or it can be set through data binding. >>> >>>In another part of his code, he is going through the grid >>>and checking the value of the checkbox for true/false >>>like this: >>> >>>For Each row As DataGridViewRow In m_Grid.Rows >>> Dim include As DataGridViewCheckBoxCell = _ >>> TryCast(row.Cells("IncludeRate"), DataGridViewCheckBoxCell) >>> If include IsNot Nothing AndAlso include.Value IsNot Nothing _ >>> AndAlso (DirectCast(include.Value, Boolean)) = True Then >>> 'Do something with the checkbox value; it's checked >>> End If >>>Next >>> >>>Hope this helps. >>>Robin S. >>>---------------------------------------------- >>> >>>"Hexman" <Hex***@binary.com> wrote in message >>>news:n0hnn2hkisjd1hm4ps1dskisskb52n83sl@4ax.com... >>>> Hello All, >>>> >>>> I'd like to find out the best way to add a cb column to a dgv and >>>> process efficiently. I see at least two ways of doing it. >>>> >>>> ------------------------------- >>>> 1) Add a cb to the dgv, iterate thru the dgv and update the bound >>>> fields if the cb has been checked. Then do the update and accept >>>> changes. How do I >>>> access the cb and its checked status? How to iterate thru dgv? >>>> >>>> Dim cbSelCol As New DataGridViewCheckBoxColumn >>>> >>>> dgv1.Columns.Insert(0, cbSelCol) >>>> With cbSelCol >>>> .HeaderText = "Select" >>>> .Name = "RecSel" >>>> .DisplayIndex = 0 >>>> .Frozen = True >>>> End With >>>> >>>> For Each dgv1????row in dgv1.rows >>>> if dgv1????row("RecSel").Checked then >>>> ...do some update process.... >>>> end if >>>> Try >>>> daEN.Update(dtEN) >>>> Catch ex As Exception >>>> 'An exception occurred >>>> End Try >>>> Next >>>> dtEN.AcceptChanges() >>>> >>>> ------------------------------- >>>> 2) Create an alias boolean field in the SELECT statement when >>>> creating >>>> the datatable. Then test the checkbox and update as applicable. >>>> How >>>> do I >>>> change the cell style to checkbox (of "RecSel")? How to test if >>>> checked? >>>> >>>> >>>> ENQrySel = "SELECT True as RecSel, ENDate, ... " >>>> "FROM ... WHERE ... ORDER BY ..." >>>> daEN.Fill(dtEN) >>>> dgv1.DataSource = dtEN >>>> >>>> DIM drEN as DataRow >>>> For Each drEN in dtEN.Rows >>>> If drEN("RecSel") ???Selected??? then >>>> ...do some update process.... >>>> End If >>>> Try >>>> daEN.Update(dtEN) >>>> Catch ex As Exception >>>> 'An exception occurred >>>> End Try >>>> Next >>>> dtEN.AcceptChanges() >>>> >>>> >>>> Which way is best/doable? Other suggestions? >>>> >>>> Thanks, >>>> >>>> Hexman >>>> >>> > 
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