具体报错内容如下：
System.InvalidOperationException:未在本地计算机上注册”
Microsoft.ACE.OLEDB.12.0"提供程序。
在
System.Data.OleDb.OleDbServicesWrapper.GetDataSource(OleDbConnectionStrin
g constr, DataSourceWrapper& datasrcWrapper)
在 System.Data.OleDb.OleDbConnectionlnternal.ctor(OleDbConnectionString
constr, OleDbConnection connection)
在
System.Data.OleDb.OleDbConnectionFactory.CreateConnection(DbConnectionOp
tions options, DbConnectionPoolKey poolKey, Object poolGroupProviderlnfo,
DbConnectionPool pool, DbConnection owningObject)
在
System.Data.ProviderBase.DbConnectionFactory.CreateConnection(DbConnection
Options options, DbConnectionPoolKey poolKey, Object poolGroupProviderlnfo
DbConnectionPool pool, DbConnection owningConnection,
DbConnectionOptions userOptions)
在
System.Data.ProviderBase.DbConnectionFactory.CreateNonPooledConnection(Db
Connection owningConnection,DbConnectionPoolGroup poolGroup,
DbConnectionOptions userOptions)
在
System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection
owningConnection,TaskCompletionSource`1 retry,DbConnectionOptions
userOptions, DbConnectioninternal oldConnection, DbConnectioninternal&
connection)
在
System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectioninternal(DbC
onnection outerConnection,DbConnectionFactory connectionFactory,
TaskCompletionSource1 retry,DbConnectionOptions userOptions)
在
System.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnectio
n outerConnection, DbConnectionFactory connectionFactory,
TaskCompletionSource'1 retry, DbConnectionOptions userOptions)
在
System.Data.ProviderBase.DbConnectioninternal.OpenConnection(DbConnection
outerConnection, DbConnectionFactory connectionFactory)
在 System.Data.OleDb.OleDbConnection.Open()
在Test.Testexcel.ExcelR(String filepath)位置 D:\...........
原因是：未安装office组件（accessdatabaseengine）
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