Question

我想过滤数据集中的值。它包含以零和非零值开头的电话号码。如何从数据集中过滤电话号码（从非零开始）。下面是vb.net代码和产生的错误。

cmd = New OracleCommand("select  PHONE from  reports.renewal_contact_t where run_date=to_date('" + TextBox1.Text + "','mm/dd/yyyy') and  EXP_DATE =to_date('" + TextBox2.Text + "','mm/dd/yyyy') and  region not in('TNP')", cn)
ada = New OracleDataAdapter(cmd)
ada.Fill(ds, "reports.renewal_contact_t ")
Dim ds1 As New DataSet
ds1.Tables("reports.renewal_contact_t").DefaultView.RowFilter = "PHONE NOT like'0'"

错误：对象引用未设置为对象的实例。 rowfilter行中的错误

Answer 1

在你的ds1中有没有表 * reports.renewal_contact_t *。将其更改为

cmd = New OracleCommand("select  PHONE from  reports.renewal_contact_t where run_date=to_date('" + TextBox1.Text + "','mm/dd/yyyy') and  EXP_DATE =to_date('" + TextBox2.Text + "','mm/dd/yyyy') and  region not in('TNP')", cn)
ada = New OracleDataAdapter(cmd)
ada.Fill(ds, "reports.renewal_contact_t")
' no need for a new dataset - as you fill ds (and not ds1)!!
ds.Tables("reports.renewal_contact_t").DefaultView.RowFilter = "PHONE NOT like'0'"

Answer 2

这将对具有类似于

的“架构”的数据集起作用

**数据示例＆gt; *

Id   Value

1    303-888-8888
2    0-418-895-9598

TryCast(filteredDS.Tables(0).Rows.Cast(Of DataRow).Where(Function(row) Not row.ItemArray(1).ToString().Substring(0, 1).Equals("0")), IEnumerable(Of DataRow)).ToList().ForEach(Sub(row) row.Delete())

- 删除手机启动时除零

以外的任何记录

从vb.net中的数据集中过滤记录

2 个答案: