比较问题 [英] Comparison problem
问题描述
嗨
我想看看
数据表中的列名称是否为空/空行。我使用以下语句来实现这一点;
If（mydatatable.Rows.Item（0）.Item（" Forenames"）=
系统.DBNull.Value.ToString）那么
我得到''运算符对类型''DBNull''和字符串"''无效。'''
以上行
错误。我做错了什么？
谢谢
问候
Hi
I am trying to see if column forenames is empty/blank in a row in a
datatable. I am using the following statement to achieve that;
If (mydatatable.Rows.Item(0).Item("Forenames") =
System.DBNull.Value.ToString) Then
I am getting the ''Operator is not valid for type ''DBNull'' and string "".''
error on the above line. What am I doing wrong?
Thanks
Regards
推荐答案
你不能使用=用于检查DBNull的运算符。相反，使用：
如果IsDBNull（mydatatable.Rows.Item（0）.Item（" Forenames"）那么
-Scott
" John"< jo ** @ nospam.infovis.co.uk>在留言中写道
新闻：OY ********** ****** @ TK2MSFTNGP11.phx.gbl ...
You can not use the "=" operator for checking DBNull. Instead, use:
If IsDBNull(mydatatable.Rows.Item(0).Item("Forenames" ) Then
-Scott
"John" <jo**@nospam.infovis.co.uk> wrote in message
news:OY****************@TK2MSFTNGP11.phx.gbl...
嗨
我试图查看列中的列名称是否为空/空白br /> datatable。我使用以下语句来实现它;
If（mydatatable.Rows.Item（0）.Item（" Forenames"）=
System.DBNull。 Value.ToString）然后
我得到的''运算符对于类型''DBNull''无效，而字符串""。''
错误在上面一行。我做错了吗？
感谢
Hi
I am trying to see if column forenames is empty/blank in a row in a
datatable. I am using the following statement to achieve that;
If (mydatatable.Rows.Item(0).Item("Forenames") =
System.DBNull.Value.ToString) Then
I am getting the ''Operator is not valid for type ''DBNull'' and string "".''
error on the above line. What am I doing wrong?
Thanks
Regards
斯科特建议：
If（mydatatable.Rows.Item（0）.Item（" Forenames"）= System.DBNull.Value）然后
-
Miha Markic - Righ tHand .NET咨询&软件开发
miha at rthand com
" John" <乔** @ nospam.infovis.co.uk>在留言中写道
新闻：OY **************** @ TK2MSFTNGP11.phx.gbl ...
As Scott suggested:
If (mydatatable.Rows.Item(0).Item("Forenames") = System.DBNull.Value) Then
--
Miha Markic - RightHand .NET consulting & software development
miha at rthand com
"John" <jo**@nospam.infovis.co.uk> wrote in message
news:OY****************@TK2MSFTNGP11.phx.gbl...
嗨
我试图查看
数据表中的列名称是否为空/空行。我使用以下语句来实现这一点;
如果（mydatatable.Rows.Item（0）.Item（" Forenames"）=
System.DBNull.Value.ToString）那么
我得到''运算符对于类型''DBNull''无效，而字符串""。''
错误在上面一行。我做错了什么？
感谢
Hi
I am trying to see if column forenames is empty/blank in a row in a
datatable. I am using the following statement to achieve that;
If (mydatatable.Rows.Item(0).Item("Forenames") =
System.DBNull.Value.ToString) Then
I am getting the ''Operator is not valid for type ''DBNull'' and string "".''
error on the above line. What am I doing wrong?
Thanks
Regards
" John" ; <乔** @ nospam.infovis.co.uk> schrieb
"John" <jo**@nospam.infovis.co.uk> schrieb
我试图在数据表中查看列名称是否为空/空行。我使用以下语句来实现这一点;
如果（mydatatable.Rows.Item（0）.Item（" Forenames"）=
System.DBNull.Value.ToString）那么
我得到的''运算符对类型''DBNull'无效，并且字符串
""。''错误在上面一行。我做错了什么？
I am trying to see if column forenames is empty/blank in a row in
a datatable. I am using the following statement to achieve that;
If (mydatatable.Rows.Item(0).Item("Forenames") =
System.DBNull.Value.ToString) Then
I am getting the ''Operator is not valid for type ''DBNull'' and string
"".'' error on the above line. What am I doing wrong?
如果mydatatable.Rows.Item（0）.Item（" Forenames"）是System.DBNull.Value那么
-
Armin
http://www.plig.net/nnq/nquote.html
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