peymannaji
جمعه 04 مرداد 1387, 21:30 عصر
با سلام ...
میخواستم بدونم مشکل کدم چی هست . با ارور Object reference not set to an instance of an object. مواجه میشم ....
Imports System.Data
Partial Class Default2
Inherits System.Web.UI.Page
Dim employee As DataTable
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If Not IsPostBack Then
GetDataTable()
End If
End Sub
Private Function GetDataTable() As DataTable
employee = New DataTable("Employee")
'Add the DataColumn using all properties
Dim eid As New DataColumn("Eid")
eid.DataType = GetType(String)
eid.MaxLength = 10
eid.Unique = True
eid.AllowDBNull = False
eid.Caption = "EID"
employee.Columns.Add(eid)
'Add the DataColumn using defaults
Dim firstName As New DataColumn("FirstName")
firstName.MaxLength = 35
firstName.AllowDBNull = False
employee.Columns.Add(firstName)
Dim lastName As New DataColumn("LastName")
lastName.AllowDBNull = False
employee.Columns.Add(lastName)
'Add the decimal DataColumn using defaults
Dim salary As New DataColumn("Salary", GetType(Decimal))
salary.DefaultValue = 0.0
employee.Columns.Add(salary)
employee.PrimaryKey = New DataColumn() {eid}
Return employee
End Function
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim newemployee As DataRow
newemployee = employee.NewRow()
newemployee("eid") = ""
newemployee("FirstName") = "Nancy"
newemployee("LastName") = "Davolio"
newemployee("Salary") = 10.0
employee.Rows.Add(newemployee)
End Sub
End Class
میخواستم بدونم مشکل کدم چی هست . با ارور Object reference not set to an instance of an object. مواجه میشم ....
Imports System.Data
Partial Class Default2
Inherits System.Web.UI.Page
Dim employee As DataTable
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If Not IsPostBack Then
GetDataTable()
End If
End Sub
Private Function GetDataTable() As DataTable
employee = New DataTable("Employee")
'Add the DataColumn using all properties
Dim eid As New DataColumn("Eid")
eid.DataType = GetType(String)
eid.MaxLength = 10
eid.Unique = True
eid.AllowDBNull = False
eid.Caption = "EID"
employee.Columns.Add(eid)
'Add the DataColumn using defaults
Dim firstName As New DataColumn("FirstName")
firstName.MaxLength = 35
firstName.AllowDBNull = False
employee.Columns.Add(firstName)
Dim lastName As New DataColumn("LastName")
lastName.AllowDBNull = False
employee.Columns.Add(lastName)
'Add the decimal DataColumn using defaults
Dim salary As New DataColumn("Salary", GetType(Decimal))
salary.DefaultValue = 0.0
employee.Columns.Add(salary)
employee.PrimaryKey = New DataColumn() {eid}
Return employee
End Function
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim newemployee As DataRow
newemployee = employee.NewRow()
newemployee("eid") = ""
newemployee("FirstName") = "Nancy"
newemployee("LastName") = "Davolio"
newemployee("Salary") = 10.0
employee.Rows.Add(newemployee)
End Sub
End Class