大家来讨论下这 SQL 语言要怎么写？ 好象有点难度

Question

用来做查询，查询的条件由编辑框输入，考虑到查询条件可以为空（全空情况我另做判断了）。所以语句我是如下写的，但有错，呵呵，大家帮忙看看    AdodcUser.RecordSource = "select * from login where " _
            & iif(trim(txtid) ="","","trim(AdodcUser.Recordset.Fields(""))="& "'" &trim(txtid)& "'") _
            & iif(trim(txtname) ="","","trim(AdodcUser.Recordset.Fields("name"))="& "'" &trim(txtname)& "'") _
            & iif(trim(txtid) ="","","trim(AdodcUser.Recordset.Fields("group"))="& "'" &trim(txtid)& "'")

Answer 1

发的有点错，重发    AdodcUser.RecordSource = "select * from login where " _
            & iif(trim(txtid) ="","","trim(AdodcUser.Recordset.Fields("id"))="& "'" &trim(txtid)& "'") _
            & iif(trim(txtname) ="","","trim(AdodcUser.Recordset.Fields("name"))="& "'" &trim(txtname)& "'")

Answer 2

trim(AdodcUser.Recordset.Fields("id"))那像上面的语句要怎么写入字符串？Fields("id")  中有引号，且 id 是表的字段名

Answer 3

按二楼意思，修改后.但在trim(AdodcUser.Recordset.Fields("id"))出错，就是由 " 引起的  Dim strid As String
    strid = ""
    If Trim(txtid) <> "" Then strid = "AdodcUser.Recordset.Fields("id") =" + "'" + Trim(txtid) + "'" + " and"
    
    Dim strname As String
    strname = ""
    If Trim(txtname) <> "" Then strname = "AdodcUser.Recordset.Fields("name") =" + "'" + Trim(txtname) + "'" + " and"
    
    Dim strqx As String
    strqx = ""
    If Trim(Comboqx.Text) <> "" Then strqx = "AdodcUser.Recordset.Fields("level") =" + "'" + Trim(Comboqx.Text) + "'"
    
    AdodcUser.RecordSource = "select * from login where " + strid + strname + strqx
    
   
    AdodcUser.Refresh

Answer 4

dim constr as string
dim conCount as long
If Trim(txtid) <> "" Then 
   concount=concount+1
   constr = "id='" & Trim(txtid) & "'"
end if
If Trim(txtname) <> "" Then
     if concount>0 then
        constr =constr &  " and  name='" & Trim(txtname) & "'" 
     else
        concount=concount+1
        constr =constr &  " name='" & Trim(txtname) & "'" 
     end if
end if
If Trim(Comboqx.Text) <> "" Then 
    if concount>0 then
        constr =constr  & " and level='" & Trim(Comboqx.Text) & "'"
    else
        constr =constr  & " level='" & Trim(Comboqx.Text) & "'"
    end if
end if
if concount>0 then
   constr=" where " & constr
end if
AdodcUser.RecordSource = "select * from login " + constr