[求助]

<P>如何在一存在的图层添加新的字段。然后通过新字段的用户输入值，提供多媒体查询？谢谢了！</P><img src="images/post/smile/dvbbs/em02.gif" />

<b>转 MO图层添加属性字段的方法
</b>Alter table structure before adding layer to Mapobjects layers collection



'*** This function Checks a dbf file for Render_ field. If it does not exists then it creates one



Public Sub subSetRenderFld(sFileName As String, sFolderName As String)

'sFileName = dbf file name without any extension

'sFolder Name = Folder where dbf file exists

On Error GoTo hErr:

Dim blnFldExits As Boolean

Dim cn As ADODB.Connection

Set cn = New ADODB.Connection

cn.Open "Driver={Microsoft Visual Foxpro Driver};SourceType=DBF;SourceDB=" ; sFolderName Dim rstSchema As ADODB.Recordset

Set rstSchema = cn.OpenSchema(adSchemaColumns, Array(Empty, Empty, sFileName ; ".dbf"))

Do Until rstSchema.EOF

If UCase(rstSchema!COLUMN_NAME) = "RENDER_" Then blnFldExits = True

rstSchema.MoveNext

Loop

rstSchema.Close

If blnFldExits = False Then cn.Execute "Alter Table [" ; sFileName

; "] Add Column " ; Strings.UCase("Render_") ; "

numeric(5,0)"



Set cn = Nothing: Set rstSchema = Nothing

Exit Sub



hErr:

MsgBox "Inside subSetRenderFld - modMapMain " ; vbCrLf ; err.Description

End Sub

<P>谢谢，但是我没有用外挂数据库，想在shp文件下的表中加，怎么加呀？</P><img src="images/post/smile/dvbbs/em01.gif" /><img src="images/post/smile/dvbbs/em02.gif" />

是不是对属性表加字段，就要借助ADO和Vfox呀？<img src="images/post/smile/dvbbs/em08.gif" />