Question

我尝试过使用DCOUNT和SQL，但没有任何工作。我在下面粘贴了两个查询。当我运行SQL时，列表框中没有任何内容。当我运行DLOOKUP时，我收到错误消息“运行时错误'2001”：您取消了以前的操作。组合框名称是ScrubbedList。表名为Scrubbed。

DCOUNT

Dim strScrubbedValue As String
strScrubbedValue = Me.ScrubbedList
Dim intCountNull As Integer

intCountNull = DCount("*", "Scrubbed", "IsNull" & strScrubbedValue)
Text267 = intCountNull

SQL

Dim strSQL As String
Dim strScrubbedValue As String

strScrubbedValue = Me.ScrubbedList
strSQL = "SELECT Count(*) As CountAll" & strScrubbedValue & " FROM Scrubbed"
strSQL = strSQL + "WHERE" & strScrubbedValue = ""
Me.List265.RowSource = strSQL

Answer 1

尝试：

 intCountNull = DCount("*", "Scrubbed", "SomeField Is Null")

所以对于组合：

 intCountNull = DCount("*", "Scrubbed", strScrubbedValue & " Is Null")

确保在连接字符串时包含相关空格非常重要。

Dim strSQL As String
Dim strScrubbedValue As String

strScrubbedValue = Me.ScrubbedList
strSQL = "SELECT Count(*) As CountAll " & strScrubbedValue & " FROM Scrubbed"
strSQL = strSQL & " WHERE " & strScrubbedValue & " Is Null"
Me.List265.RowSource = strSQL

请注意，Null和零长度字符串（ZLS）不相同。

为了得到这两者，你可以说：

    strSQL = strSQL & " WHERE " & strScrubbedValue & " & '' = ''"

VBA中的字符串连接符是＆amp;而不是+。必须小心使用加号，因为它可能导致意外的空值。

如何在组合框中选择的字段中显示空值的计数？

1 个答案: