已经是一个与此命令关联的开放DataReader，必须先关闭它 [英] already an open DataReader associated with this Command which must be closed first
问题描述
i得到错误：
"已经有一个与此命令关联的开放DataReader必须
先关闭
谢谢
巴特
--------------- --------------------------
进口System.Data.sqlclient
进口系统.Data
....
....
sql =" SELECT count（*）FROM pc where lokl ='' " &安培; w& "'';"
comd =新的SqlCommand（sql，oConnection）
recpc = comd.ExecuteScalar
sql =" SELECT pcnr FROM pc其中lokl =''" &安培; w& "'';"
comd =新的SqlCommand（sql，oConnection）
dtreader = comd.ExecuteReader
for j = 1要重新计算
dtreader.Read（）
ww = dtreader.GetValue（0）
sql =" INSERT INTO mytable（ field1值（& ww&"）"
comd.ExecuteNonQuery（）
下一页
dtreader .Close（）
-------------------------------------- -------------------------
创建另一个命令对象用于运行插入：
sql =" INSERT INTO mytable（field1 values（& ww&"）"
comd1 =新的SqlCommand（sql，oConnection）
comd1.ExecuteNonQuery（）
-
Eliyahu Goldin，
软件开发人员和顾问
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
" Bart" < b@sdq.dcwrote in message
news：uk ************** @ TK2MSFTNGP02.phx.gbl ...
i得到错误：
"已经有一个与此命令关联的开放DataReader，其中
必须
先关闭
谢谢
巴特
----------------------------------- ------
Imports System.Data.sqlclient
Imports System.Data
...
...
sql =" SELECT count（*）FROM pc其中lokl =''" &安培; w& "'';"
comd =新的SqlCommand（sql，oConnection）
recpc = comd.ExecuteScalar
sql =" SELECT pcnr FROM pc其中lokl =''" &安培; w& "'';"
comd =新的SqlCommand（sql，oConnection）
dtreader = comd.ExecuteReader
for j = 1要重新计算
dtreader.Read（）
ww = dtreader.GetValue（0）
sql =" INSERT INTO mytable（ field1值（& ww&"）"
comd.ExecuteNonQuery（）
下一页
dtreader .Close（）
-------------------------------------- -------------------------
< blockquote>thansk回复
我做了这个：
sql =" SELECT count（*）FROM pc where lokl =' '"& w&"'';"
comd =新的SqlCommand（sql，oConnection）
recpc = comd.ExecuteScalar
sql =" SELECT pcnr FROM pc where lokl =''"& w&"'';"
comd = New SqlCommand（sql，oConnection） ）
dtreader = comd.ExecuteReader
对于j = 1要重新计算
dtreader.Read（）
ww = dtreader.GetValue（0）
sql =" INSERT INTO mytable （field1值（"） &安培; ww& "）"
comd1 =新的SqlCommand（sql，oConnection）
comd1.ExecuteNonQuery（）
下一页
dtreader.Close（）
但行仍然是同样的错误：comd1.ExecuteNonQuery（）
" Eliyahu Goldin" < RE ************************** @ mMvVpPsS.orgschree f
bericht新闻：OB *** ********** @ TK2MSFTNGP02.phx.gbl ...
创建另一个用于运行插入的命令对象：
sql =" INSERT INTO mytable（field1 values（"& ww&"）"
comd1 = New SqlCommand（sql，oConnection）
comd1.ExecuteNonQuery（）
-
Eliyahu Goldin，
软件开发人员和顾问
Microsoft MVP [ASP.NET]
http：// msmvps。 com / blogs / egoldin
在
之前需要重新构造代码以关闭第一个datareader
开始在同一个连接上使用另一个。只有一个请求可以是
当时服务，直到第一个读者关闭它不会让任何人
要运行。
-
Eliyahu Goldin，
软件开发人员&顾问
Microsoft MVP [ASP.NET]
http： //msmvps.com/blogs/egoldin
" Bart" < b@sdq.dcwrote in message
news：Og ************** @ TK2MSFTNGP02.phx.gbl ...
thansk回复
我这样做了：
sql =" SELECT count（* ）FROM pc其中lokl =''" &安培; w& "'';"
comd =新的SqlCommand（sql，oConnection）
recpc = comd.ExecuteScalar
sql =" SELECT pcnr FROM pc其中lokl =''" &安培; w& "'';"
comd =新的SqlCommand（sql，oConnection）
dtreader = comd.ExecuteReader
For j = 1要重新计算
dtreader.Read（）
ww = dtreader.GetValue（0）
sql =" INSERT INTO mytable（ field1值（& ww&"）"
comd1 =新的SqlCommand（sql，oConnection）
comd1.ExecuteNonQuery（）
下一页
dtreader.Close（）
但行仍然是同样的错误：comd1.ExecuteNonQuery（）
Eliyahu Goldin< RE ************************** @ mMvVpPsS.orgschree f in
bericht新闻：OB ************* @ TK2MSFTNGP02.phx.gbl ...
创建另一个命令对象来运行insert：
sql =" INSERT INTO mytable（field1 values（"& ww&"）"
comd1 =新的SqlCommand（sql，oConnection）
comd1.ExecuteNonQuery（）
-
Eliyahu Goldin，
软件开发人员&顾问
Microsoft MVP [ASP.NET]
http： //msmvps.com/blogs/egoldin
Hi,
i get the error:
"There is already an open DataReader associated with this Command which must
be closed first"
Thanks
Bart
-----------------------------------------
Imports System.Data.sqlclient
Imports System.Data
....
....
sql = "SELECT count(*) FROM pc where lokl=''" & w & "'';"
comd = New SqlCommand(sql, oConnection)
recpc = comd.ExecuteScalar
sql = "SELECT pcnr FROM pc where lokl=''" & w & "'';"
comd = New SqlCommand(sql, oConnection)
dtreader = comd.ExecuteReader
for j = 1 To recpc
dtreader.Read()
ww = dtreader.GetValue(0)
sql = "INSERT INTO mytable (field1 values(" & ww & ")"
comd.ExecuteNonQuery()
Next
dtreader.Close()
---------------------------------------------------------------
Create another command object for running the insert:
sql = "INSERT INTO mytable (field1 values(" & ww & ")"
comd1 = New SqlCommand(sql, oConnection)
comd1.ExecuteNonQuery()
--
Eliyahu Goldin,
Software Developer & Consultant
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
"Bart" <b@sdq.dcwrote in message
news:uk**************@TK2MSFTNGP02.phx.gbl...Hi,
i get the error:
"There is already an open DataReader associated with this Command whichmust
be closed first"
Thanks
Bart
-----------------------------------------
Imports System.Data.sqlclient
Imports System.Data
...
...
sql = "SELECT count(*) FROM pc where lokl=''" & w & "'';"
comd = New SqlCommand(sql, oConnection)
recpc = comd.ExecuteScalar
sql = "SELECT pcnr FROM pc where lokl=''" & w & "'';"
comd = New SqlCommand(sql, oConnection)
dtreader = comd.ExecuteReader
for j = 1 To recpc
dtreader.Read()
ww = dtreader.GetValue(0)
sql = "INSERT INTO mytable (field1 values(" & ww & ")"
comd.ExecuteNonQuery()
Next
dtreader.Close()
---------------------------------------------------------------
Hi, thansk for replying
I did this:
sql = "SELECT count(*) FROM pc where lokl=''" & w & "'';"
comd = New SqlCommand(sql, oConnection)
recpc = comd.ExecuteScalar
sql = "SELECT pcnr FROM pc where lokl=''" & w & "'';"
comd = New SqlCommand(sql, oConnection)
dtreader = comd.ExecuteReader
For j = 1 To recpc
dtreader.Read()
ww = dtreader.GetValue(0)
sql = "INSERT INTO mytable (field1 values(" & ww & ")"
comd1 = New SqlCommand(sql, oConnection)
comd1.ExecuteNonQuery()
Next
dtreader.Close()
but still same error at line: comd1.ExecuteNonQuery()
"Eliyahu Goldin" <RE**************************@mMvVpPsS.orgschree f in
bericht news:OB*************@TK2MSFTNGP02.phx.gbl...Create another command object for running the insert:
sql = "INSERT INTO mytable (field1 values(" & ww & ")"
comd1 = New SqlCommand(sql, oConnection)
comd1.ExecuteNonQuery()
--
Eliyahu Goldin,
Software Developer & Consultant
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
You need to re-structure the code to close the first datareader before
starting using another one on the same connection. Only one request can be
served at the time and untill the first reader closes it won''t let anyone
else to run.
--
Eliyahu Goldin,
Software Developer & Consultant
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
"Bart" <b@sdq.dcwrote in message
news:Og**************@TK2MSFTNGP02.phx.gbl...Hi, thansk for replying
I did this:
sql = "SELECT count(*) FROM pc where lokl=''" & w & "'';"
comd = New SqlCommand(sql, oConnection)
recpc = comd.ExecuteScalar
sql = "SELECT pcnr FROM pc where lokl=''" & w & "'';"
comd = New SqlCommand(sql, oConnection)
dtreader = comd.ExecuteReader
For j = 1 To recpc
dtreader.Read()
ww = dtreader.GetValue(0)
sql = "INSERT INTO mytable (field1 values(" & ww & ")"
comd1 = New SqlCommand(sql, oConnection)
comd1.ExecuteNonQuery()
Next
dtreader.Close()
but still same error at line: comd1.ExecuteNonQuery()
"Eliyahu Goldin" <RE**************************@mMvVpPsS.orgschree f in
bericht news:OB*************@TK2MSFTNGP02.phx.gbl...Create another command object for running the insert:
sql = "INSERT INTO mytable (field1 values(" & ww & ")"
comd1 = New SqlCommand(sql, oConnection)
comd1.ExecuteNonQuery()
--
Eliyahu Goldin,
Software Developer & Consultant
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
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