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每个变量值是否为空的判断 发帖心情

Post By：2017/2/6 11:35:00 [只看该作者]

比如有5个变量A,B,C,D,E.

需要考虑全部为空的情况，全部不为空。

if A="" and B=“” and C="" and D="" and E="" then

代码

elseif A<>"" and B<>“” and C<>"" and D<>"" and E<>"" then

代码

end if

但还有比如A为空，其他4个不为空。A,B为空，其他3个不为空，等等

一个一个写if else是不是太多了，也容易出错。

有什么办法可以做到，只需要判断5个变量不为空的写代码。

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Post By：2017/2/6 13:35:00 [只看该作者]

直接说你要做什么。逻辑是什么。一般，这样判断

Dim str As String = ""

If A <> "" Then

str &= "A不为空,"

End If

If B <> "" Then

str &= "B不为空,"

End If

If C <> "" Then

str &= "C不为空,"

End If

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Post By：2017/2/6 15:18:00 [只看该作者]

<WebMethod()>

Public Function Detailedquery(ByVal scddhm As String, ByVal gdhh As String, ByVal wlbm As String, ByVal kwlb As String, ByVal startdate As String, ByVal enddate As String) As String

Dim cnStr As String = "Data Source=172.16.11.201;Initial Catalog=songjiang;Integrated Security=False;User ID=sa;Password=bdcom103liujy;"

Dim cn As New SqlClient.SqlConnection(cnStr)

cn.Open()

Dim state As String = ""

If scddhm = "" And gdhh = "" And wlbm = "" And kwlb = "" And startdate = "" And enddate = "" Then

Dim adapter As New SqlClient.SqlDataAdapter("s elect * from [可用数量表]", cn)

Dim dt As New DataTable

adapter.Fill(dt)

cn.Close()

For Each dr As DataRow In dt.Rows

state &= "生产订单号码:" & dr("生产订单号码") & "工单行号:" & dr("工单行号") & "物料编码:" & dr("物料编码") & "库位类别:" & dr("库位类别") & "入库时间:" & dr("入库时间") & "|"

ElseIf scddhm <> "" And gdhh <> "" And wlbm <> "" And kwlb <> "" And startdate <> "" And enddate <> "" Then

Dim adapter As New SqlClient.SqlDataAdapter("se lect * from [可用数量表] where 生产订单号码 = '" & scddhm & "' and 工单行号 = '" & gdhh & "' and 物料编码 = '" & wlbm & "' and 库位类别 = '" & kwlb & "' and 入库时间 >= '" & startdate & "' and 入库时间 <= '" & enddate & "' ", cn)

Dim dt As New DataTable

adapter.Fill(dt)

cn.Close()

For Each dr As DataRow In dt.Rows

End If

Return state

End Function

红色代码是条件。但这仅仅是2个分支，其他分支怎么弄，针对每一个不为空的都要判断一下。

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Post By：2017/2/6 15:23:00 [只看该作者]

红色代码，你复制多段即可。

Dim filter As String = "1=1"
If r.isnull("一级地址") Then
filter &= " and 一级地址 is null"
Else
filter &= " and 一级地址 = '" & r("一级地址") & "'"
End If
Dim dr As DataRow = DataTables("五级地址网格关联表").Find(filter)

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Post By：2017/2/6 16:46:00 [只看该作者]

Public Function Detailedquery(ByVal scddhm As String, ByVal gdhh As String, ByVal wlbm As String, ByVal kwlb As String, ByVal startdate As String, ByVal enddate As String) As String

Dim cnStr As String = "Data Source=172.16.11.201;Initial Catalog=songjiang;Integrated Security=False;User ID=sa;Password=bdcom103liujy;"

Dim cn As New SqlClient.SqlConnection(cnStr)

cn.Open()

Dim state As String = ""

Dim filter As String = "1=1"

If scddhm = "" And gdhh = "" And wlbm = "" And kwlb = "" And startdate = "" And enddate = "" Then

Dim adapter1 As New SqlClient.SqlDataAdapter("s elect * from [可用数量表]", cn)

Dim dt As New DataTable

adapter1.Fill(dt)

cn.Close()

For Each dr As DataRow In dt.Rows

Return state

Else

If scddhm <> "" Then

filter &= "and 生产订单号码 = '" & scddhm & "' "

Else

End If

If gdhh <> "" Then

filter &= "and 工单行号 = '" & gdhh & "'"

End If

If wlbm <> "" Then

filter &= "and 物料编码 = '" & wlbm & "'"

End If

If kwlb <> "" Then

filter &= "库位类别 = '" & kwlb & "'"

End If

If startdate <> "" Then

filter &= "入库时间 >= '" & startdate & "'"

End If

If enddate <> "" Then

filter &= "入库时间 <= '" & enddate & "'"

End If

Dim adapter As New SqlClient.SqlDataAdapter("s elect * from [可用数量表] where filter", cn)

Dim dt As New DataTable

adapter.Fill(dt)

cn.Close()

For Each dr As DataRow In dt.Rows

Return state

End If

End Function

报这个错误:System.Data.SqlClient.SqlException: 在应使用条件的上下文(在 'filter' 附近)中指定了非布尔类型的表达式。

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Post By：2017/2/6 16:49:00 [只看该作者]

Dim adapter As New SqlClient.SqlDataAdapter("select * from [可用数量表] where " & filter, cn)

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Post By：2017/2/6 17:25:00 [只看该作者]

<WebMethod()>

Public Function Detailedquery(ByVal scddhm As String, ByVal gdhh As String, ByVal wlbm As String, ByVal kwlb As String, ByVal startdate As String, ByVal enddate As String) As String

Dim cnStr As String = "Data Source=172.16.11.201;Initial Catalog=songjiang;Integrated Security=False;User ID=sa;Password=bdcom103liujy;"

Dim cn As New SqlClient.SqlConnection(cnStr)

cn.Open()

Dim state As String = ""

If scddhm = "" And gdhh = "" And wlbm = "" And kwlb = "" And startdate = "" And enddate = "" Then

Dim adapter1 As New SqlClient.SqlDataAdapter("s elect * from [可用数量表]", cn)

Dim dt As New DataTable

adapter1.Fill(dt)

cn.Close()

For Each dr As DataRow In dt.Rows

Return state

Else

Dim filter As String = "1=1"

If scddhm <> "" Then

Filter &= "and 生产订单号码 = '" & scddhm & "' "

Else

End If

If gdhh <> "" Then

Filter &= "and 工单行号 = '" & gdhh & "'"

End If

If wlbm <> "" Then

Filter &= "and 物料编码 = '" & wlbm & "'"

End If

If kwlb <> "" Then

Filter &= "库位类别 = '" & kwlb & "'"

End If

If startdate <> "" Then

Filter &= "入库时间 >= '" & startdate & "'"

End If

If enddate <> "" Then

Filter &= "入库时间 <= '" & enddate & "'"

End If

Dim adapter As New SqlClient.SqlDataAdapter("s elect * from [可用数量表] where" & filter, cn)

Dim dt As New DataTable

adapter.Fill(dt)

cn.Close()

For Each dr As DataRow In dt.Rows

Return state

End If

End Function

报System.Data.SqlClient.SqlException: '=' 附近有语法错误。是哪里出错呢?

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Post By：2017/2/6 17:27:00 [只看该作者]

Dim filter As String = "1=1"

If scddhm <> "" Then

Filter &= " and 生产订单号码 = '" & scddhm & "' "

Else

End If

If gdhh <> "" Then

Filter &= " and 工单行号 = '" & gdhh & "'"

End If

If wlbm <> "" Then

Filter &= " and 物料编码 = '" & wlbm & "'"

End If

If kwlb <> "" Then

Filter &= " and 库位类别 = '" & kwlb & "'"

End If

If startdate <> "" Then

Filter &= " and 入库时间 >= '" & startdate & "'"

End If

If enddate <> "" Then

Filter &= " and 入库时间 <= '" & enddate & "'"

End If

Dim adapter As New SqlClient.SqlDataAdapter("s elect * from [可用数量表] where " & filter, cn)

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