VB.Net - 如何检查主键是否存在于 Access DB 中

Question

我想使用 VB.Net 和 VB.Net 检查 Access 数据库是否存在主键。 OleDb：

• 按主键名称

• 按作为主键的字段数量

Answer 1

来自此处 ：

Public Shared Function getKeyNames(tableName As [String], conn As DbConnection) As List(Of String)
    Dim returnList = New List(Of String)()


    Dim mySchema As DataTable = TryCast(conn, OleDbConnection).GetOleDbSchemaTable(OleDbSchemaGuid.Primary_Keys, New [Object]() {Nothing, Nothing, tableName})


    ' following is a lengthy form of the number '3' :-)
    Dim columnOrdinalForName As Integer = mySchema.Columns("COLUMN_NAME").Ordinal

    For Each r As DataRow In mySchema.Rows
        returnList.Add(r.ItemArray(columnOrdinalForName).ToString())
    Next

    Return returnList
End Function