丢弃数据集中的行。 [英] Discarding rows in dataset.

问题描述

大家好，


有人能够告诉我从数据集中删除

不需要的行的最优雅方式更新前的情况？或者，

在将行初始添加到

记录集后将所有行重置为未更改。


我创建了一个数据集，在初始.Fill之后开始为空。


然后我用一些默认信息创建几行，留下一个

关键信息值为0;


dr = ds.Tables（" mytable"）。NewRow（）

带博士

.Item（" basicdata1" ;）= myvalue1

.Item（" basicdata2"）= myvalue2

.Item（" criticaldata"）= 0

。项目（" created"）=现在（）

结束

ds.Tables（" mytable"）。Rows.Add（dr）


然后，我的更新做了类似的事情;


da.Update（ds，" mytable"）


全部非常基本的东西......但我想要的是只将新行

插入到具有criticaldata的数据库中。值<> 0并弃掉

休息。我可以使用GetChanges方法，如果我知道如何在创建后立即将行标记为

''不变' - 但不知道如何。


任何帮助将不胜感激。

谢谢，


格雷厄姆

Hi all,

Would someone be able to tell me the most ''graceful'' way of removing
unwanted rows from a dataset based on a condition prior to update? OR,
resetting the rows all to unchanged after they are initally added to the
recordset.

I create a dataset, which begins empty after the initial .Fill.

Then I create several rows with some default information, leaving one
critical piece of information value as 0;

dr = ds.Tables("mytable").NewRow()
With dr
.Item("basicdata1") = myvalue1
.Item("basicdata2") = myvalue2
.Item("criticaldata") = 0
.Item("created") = Now()
End With
ds.Tables("mytable").Rows.Add(dr)

Then, my update does something like;

da.Update(ds, "mytable")

All pretty basic stuff.... but what I would like is to ONLY insert new rows
into the database that have a "criticaldata" value <> 0 and discard the
rest. I could use the GetChanges method if I knew how to mark the rows as
''unchanged'' immediately after creation - but don''t know how.

Any help would be greatly appreciated.
Thanks,

Graham

推荐答案

你可以使用GetChanges获取RowState或添加的行。然后

在GetChanges表上调用更新 - 然后在原始上接受更改

-

WG Ryan MVP Windows - Embedded


对微软嵌入式新闻组的有效性有意见吗？

让微软知道！
https://www.windowsembeddedeval.com/...ity/newsgroups

" Graham Blandford" < GR ************** @ sympatico.ca>在消息中写道

news：tH ********************* @ news20.bellglobal.com ...

YOu can use GetChanges and just get the rows with RowState or added. Then
call update on the GetChanges table - then acceptChanges on the original
--
W.G. Ryan MVP Windows - Embedded

Have an opinion on the effectiveness of Microsoft Embedded newsgroups?
Let Microsoft know!
https://www.windowsembeddedeval.com/...ity/newsgroups
"Graham Blandford" <gr**************@sympatico.ca> wrote in message
news:tH*********************@news20.bellglobal.com ...

根据更新前的情况，有人能告诉我从数据集中删除不需要的行的最优雅方式吗？或者，
在将行初始添加到
记录集后将所有行重置为未更改。

我创建了一个数据集，在初始.Fill之后开始为空。

然后我用一些默认信息创建几行，将一个
关键信息值保留为0;

dr = ds.Tables（" mytable"）。NewRow （）
随着
.Item（" basicdata1"）= myvalue1
.Item（" basicdata2"）= myvalue2
.Item（" criticaldata"）= 0
.Item（" created"）= Now（）
结束
ds.Tables（" mytable"）。Rows.Add（dr）

然后，我的更新做了类似的事情;

da.Update（ds，mytable）

所有非常基本的东西....但我想要的是只需将新的
行插入到具有criticaldata的数据库中。值<> 0并丢弃
休息。我可以使用GetChanges方法，如果我知道如何在创建后立即将行标记为未更改 - 但不知道如何。

任何帮助将不胜感激。
谢谢，

格雷厄姆

Hi all,

Would someone be able to tell me the most ''graceful'' way of removing
unwanted rows from a dataset based on a condition prior to update? OR,
resetting the rows all to unchanged after they are initally added to the
recordset.

I create a dataset, which begins empty after the initial .Fill.

Then I create several rows with some default information, leaving one
critical piece of information value as 0;

dr = ds.Tables("mytable").NewRow()
With dr
.Item("basicdata1") = myvalue1
.Item("basicdata2") = myvalue2
.Item("criticaldata") = 0
.Item("created") = Now()
End With
ds.Tables("mytable").Rows.Add(dr)

Then, my update does something like;

da.Update(ds, "mytable")

All pretty basic stuff.... but what I would like is to ONLY insert new rows into the database that have a "criticaldata" value <> 0 and discard the
rest. I could use the GetChanges method if I knew how to mark the rows as
''unchanged'' immediately after creation - but don''t know how.

Any help would be greatly appreciated.
Thanks,

Graham

我猜row.AcceptChanges会做。


" Graham Blandford" < GR ************** @ sympatico.ca>在消息中写道

news：tH ********************* @ news20.bellglobal.com ...

I guess row.AcceptChanges will do.

"Graham Blandford" <gr**************@sympatico.ca> wrote in message
news:tH*********************@news20.bellglobal.com ...

根据更新前的情况，有人能告诉我从数据集中删除不需要的行的最优雅方式吗？或者，
在将行初始添加到
记录集后将所有行重置为未更改。

我创建了一个数据集，在初始.Fill之后开始为空。

然后我用一些默认信息创建几行，将一个
关键信息值保留为0;

dr = ds.Tables（" mytable"）。NewRow （）
随着
.Item（" basicdata1"）= myvalue1
.Item（" basicdata2"）= myvalue2
.Item（" criticaldata"）= 0
.Item（" created"）= Now（）
结束
ds.Tables（" mytable"）。Rows.Add（dr）

然后，我的更新做了类似的事情;

da.Update（ds，mytable）

所有非常基本的东西....但我想要的是只需将新的
行插入到具有criticaldata的数据库中。值<> 0并丢弃
休息。我可以使用GetChanges方法，如果我知道如何在创建后立即将行标记为未更改 - 但不知道如何。

任何帮助将不胜感激。
谢谢，

格雷厄姆

Hi all,

Would someone be able to tell me the most ''graceful'' way of removing
unwanted rows from a dataset based on a condition prior to update? OR,
resetting the rows all to unchanged after they are initally added to the
recordset.

I create a dataset, which begins empty after the initial .Fill.

Then I create several rows with some default information, leaving one
critical piece of information value as 0;

dr = ds.Tables("mytable").NewRow()
With dr
.Item("basicdata1") = myvalue1
.Item("basicdata2") = myvalue2
.Item("criticaldata") = 0
.Item("created") = Now()
End With
ds.Tables("mytable").Rows.Add(dr)

Then, my update does something like;

da.Update(ds, "mytable")

All pretty basic stuff.... but what I would like is to ONLY insert new rows into the database that have a "criticaldata" value <> 0 and discard the
rest. I could use the GetChanges method if I knew how to mark the rows as
''unchanged'' immediately after creation - but don''t know how.

Any help would be greatly appreciated.
Thanks,

Graham

Graham，

In除了使用DataRowState的GetChanges，你可以使用

DataTable.Select。


我会推荐DataTable.Select，因为你返回了对
的引用现有DataSet中的
行，其中GetChanges将返回一个新的DataSet

（带有新行）。


David Sceppa解释了它们之间的区别GetChanges&当你打算在他的书Microsoft ADO.NET - Core

Reference中更新数据库时，选择你想要更新数据库。来自MS

按。


如果你在ADO.NET上做了很多我强烈推荐Sceppa的书，

这是一个关于ADO.NET的好教程以及一个很好的桌面参考一次

你知道ADO.NET。


希望这有助于

Jay

" Graham Blandford" < GR ************** @ sympatico.ca>在消息中写道

news：tH ********************* @ news20.bellglobal.com ...

Graham,
In addition to GetChanges with the DataRowState you can use
DataTable.Select.

I would recommend DataTable.Select as you are returned references to the
rows in the existing DataSet, where as GetChanges will return a new DataSet
(with new rows).

David Sceppa explains the difference between GetChanges & Select when you
intend on updating the database in his book "Microsoft ADO.NET - Core
Reference" from MS
Press.

If you are doing a lot with ADO.NET I strongly recommend Sceppa''s book,
which is a good tutorial on ADO.NET as well as a good desk reference once
you know ADO.NET.

Hope this helps
Jay
"Graham Blandford" <gr**************@sympatico.ca> wrote in message
news:tH*********************@news20.bellglobal.com ...

根据更新前的情况，有人能告诉我从数据集中删除不需要的行的最优雅方式吗？或者，
在将行初始添加到
记录集后将所有行重置为未更改。

我创建了一个数据集，在初始.Fill之后开始为空。

然后我用一些默认信息创建几行，将一个
关键信息值保留为0;

dr = ds.Tables（" mytable"）。NewRow （）
随着
.Item（" basicdata1"）= myvalue1
.Item（" basicdata2"）= myvalue2
.Item（" criticaldata"）= 0
.Item（" created"）= Now（）
结束
ds.Tables（" mytable"）。Rows.Add（dr）

然后，我的更新做了类似的事情;

da.Update（ds，mytable）

所有非常基本的东西....但我想要的是只需将新的
行插入到具有criticaldata的数据库中。值<> 0并丢弃
休息。我可以使用GetChanges方法，如果我知道如何在创建后立即将行标记为未更改 - 但不知道如何。

任何帮助将不胜感激。
谢谢，

格雷厄姆

Hi all,

Would someone be able to tell me the most ''graceful'' way of removing
unwanted rows from a dataset based on a condition prior to update? OR,
resetting the rows all to unchanged after they are initally added to the
recordset.

I create a dataset, which begins empty after the initial .Fill.

Then I create several rows with some default information, leaving one
critical piece of information value as 0;

dr = ds.Tables("mytable").NewRow()
With dr
.Item("basicdata1") = myvalue1
.Item("basicdata2") = myvalue2
.Item("criticaldata") = 0
.Item("created") = Now()
End With
ds.Tables("mytable").Rows.Add(dr)

Then, my update does something like;

da.Update(ds, "mytable")

All pretty basic stuff.... but what I would like is to ONLY insert new rows into the database that have a "criticaldata" value <> 0 and discard the
rest. I could use the GetChanges method if I knew how to mark the rows as
''unchanged'' immediately after creation - but don''t know how.

Any help would be greatly appreciated.
Thanks,

Graham

这篇关于丢弃数据集中的行。的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！