Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load if ispostback then DataGrid.DataSource = CreateSource() DataGrid.DataBind() end if end sub Private Function CreateSource() As DataView Dim dt As New DataTable() Dim dr As DataRow Dim i As Integer dt.Columns.Add("ClassID") dt.Columns.Add("CourseID") dt.Columns.Add("CourseName") dt.Columns.Add("SessionID") dt.Columns.Add("SessionDescription") dt.Columns.Add("ScheduleBeginTime") dt.Columns.Add("Classroom") dt.Columns.Add("SessionHours") For i = 0 To 9 dr = dt.NewRow dr("ClassID") = "" dr("CourseID") = "" dr("CourseName") = "" dr("SessionID") = "" dr("SessionDescription") = "" dr("ScheduleBeginTime") = "" dr("Classroom") = "" dr("SessionHours") = "" dt.Rows.Add(dr) Next CreateSource = New DataView(dt) End Function
if ispostback then
DataGrid.DataSource = CreateSource()
DataGrid.DataBind()
end if
end sub
Private Function CreateSource() As DataView
Dim dt As New DataTable()
Dim dr As DataRow
Dim i As Integer
dt.Columns.Add("ClassID")
dt.Columns.Add("CourseID")
dt.Columns.Add("CourseName")
dt.Columns.Add("SessionID")
dt.Columns.Add("SessionDescription")
dt.Columns.Add("ScheduleBeginTime")
dt.Columns.Add("Classroom")
dt.Columns.Add("SessionHours")
For i = 0 To 9
dr = dt.NewRow
dr("ClassID") = ""
dr("CourseID") = ""
dr("CourseName") = ""
dr("SessionID") = ""
dr("SessionDescription") = ""
dr("ScheduleBeginTime") = ""
dr("Classroom") = ""
dr("SessionHours") = ""
dt.Rows.Add(dr)
Next
CreateSource = New DataView(dt)
End Function
例子:
using System;
using System.Data.SqlTypes;
public class TestClass
{
object dValue = DBNull.Value
try
{
dValue = double.Parse(this.txtbox.Text);
}
catch{}
}
反正也不管它是什么类型。
我在使用的时候,是对double类型的变量赋值的,如果产生异常,即输入的值不为数值,就加入空值。