判断字段是否存在

[清海扬波]

if Rs.Fields("字段") then
.....
end if
我这个字段有时候有,有时候没有的,现在就是判断它有没有,然后处理,但是怎么判断呢?

[fxy_2002]

haveField=false
for each i in rs.fields
if i.name="字段" then
haveField=true
exit for
end if
next

if haveField then msgbox "字段存在！"

[hongqi162]

循环一下Fields判断Rs.Fields.Item(index).Name

[云路]

顶楼上的.
另外
如果sql数据库可以查数据库表
select * from syscolumns a,sysobjects b where a.id=b.id and a.name='字段' and b.name='表'

[bbhere]

dim fld as Field
for each fld in rs.fields
if fld.name="字段" then
msgbox "字段存在!"
exit for
end if
next

[of123]

Dim cn As ADODB.Connection, rs As ADODB.Recordset
Dim i As Integer
Dim TheFieldExisting As Boolean
Dim strField As String

Set cn = New ADODB.Connection
cn.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\Program Files\Microsoft Visual Studio\VB98\BIBLIO.MDB;Persist Security Info=False"
cn.Open

Set rs = New ADODB.Recordset
rs.Open ("SELECT * FROM titles"), cn

'方法一
For i = 0 To rs.Fields.Count - 1
If UCase(rs.Fields(i).Name) = "TITLE" Then
TheFieldExisting = True
Exit For
End If
Next i
MsgBox "Field [Title] " & IIf(TheFieldExisting, "", "Not ") & "in Place"

'方法二
On Error Resume Next
strField = rs!UserName
If Err.Number = 3265 Then TheFieldExisting = False
MsgBox "Field [UserName] " & IIf(TheFieldExisting, "", "Not ") & "in Place"

[清海扬波]

先试试!!!但是感觉这样我字段多不是很慢!!!有更简便的方法没?

[fxy_2002]

一个表最多255个字段，你认为一个255次的循环对电脑来说会是一个负担么？只需要0.000000001ms而已！:-P

[清海扬波]

呵呵,我现在有7个字段,怎么样在产生了3265之后还原err.number啊,现在好象一个出错后面的err.number就不变了

[清海扬波]

问题解决,呵呵