如何将sql数据库中某个字段的值赋值给一个数组,急,请高手相助!
代码如下:
Dim a() As Single ‘定义动态数组
Dim i As Integer = 0
Dim strsql As String
Dim sqlcon As New SqlConnection("database=computer;initial catalog=数据库名;Integrated Security=SSPI")
Dim sqlcom As New SqlClient.SqlCommand ' 声明一个SqlCommand变量
Dim sqldr As SqlClient.SqlDataReader ' 声明一个SqlDataReader变量
Try
Dim date1, date2 As Date ’声明查询的开始和结束时间
date1 = Convert.ToDateTime(DateTimePicker1.Text) ‘将开始时间赋给data1
date2 = Convert.ToDateTime(DateTimePicker2.Text)
strsql = "select 位移 from 多点位移计原始测值表 where 测时 >= '" + Trim(date1) + "' and 测时 <= '" + Trim(date2) + "' "
sqlcom.Connection = sqlcon
sqlcom.CommandText = strsql
sqlcon.Open()
sqldr = sqlcom.ExecuteReade(CommandBehavior.CloseConnection)
Do Until sqldr.Read = False
’我个人认为问题在下面的语句
a(i) = Convert.ToSingle(sqldr("字段"))
i += 1
Loop
sqldr.Close()
sqlcon.Close()
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End If
运行后提示是“未将对象设置为对象的实例”,由于本人是新手,又急于要从数据库中读出数据赋给数组后做计算用,所以请各位高手帮忙,问题解决,高分送上!!!