他总是提示,未将对象引用设置到对象的实例

[kanes]

Dim i, x As Integer
Dim temp_kfs(,)
i = 0
Do While dr_kfs.Read
temp_kfs(i, 1) = dr_kfs.Item("kfs_id") '这句就出错了.
temp_kfs(i, 2) = dr_kfs.Item("kfsname")
i = i + 1
Loop
dr_kfs.Close()
conn.Close()

[saucer]

you didn't define temp_kfs' dimension, try

Dim temp_kfs(100,100)

[一起学习前端吧]

dr_kfs在哪儿定义得呀？

[AustinLei]

Dim i, x As Integer
Dim temp_kfs(,)
Dim dr_kfs As New DataReader
i = 0
//在此写从数据库读数据的代码
Do While dr_kfs.Read
temp_kfs(i, 1) = dr_kfs.Item("kfs_id") '这句就出错了.
temp_kfs(i, 2) = dr_kfs.Item("kfsname")
i = i + 1
Loop
dr_kfs.Close()
conn.Close()

[kanes]

dr_kfs我在上面定义好了.dim dr_kfs As SqlClient.SqlDataReader

[kanes]

思归大哥.我按你的意思定义了上下标,程序果然不错了,可是这不是长久之计呀.因为我的数据以后会多起来的,要是超过100的上标那我怎么办.

[saucer]

look into
redim preserve

[kanes]

思归大哥呀.dr_kfs As SqlClient.SqlDataReader
这个控能不能得到dr_kfs的记录条数呀.

[saucer]

SqlDataReader is a forward only stream, you can only get the 记录条数 at the end of stream

if you need to know 记录条数 righ away, use SqlDataAdapter and DataSet/DataTable

[kanes]

SqlDataAdapter,DataSet,DataTable,SqlDataReader这几种数据集,到底有什么区别吗?他们是如何区分应用呢.

[saucer]

I would suggest you read a book on ADO.NET, or see

Contrasting the ADO.NET DataReader and DataSet
http://msdn.microsoft.com/msdnmag/issues/04/06/DataPoints/default.aspx