Question

Asp.net vb网页制做问题

我想做一个留言版，怎么将cookie变量插入数据库，这个是插入按钮代码：
Sub Sure_Click(Sender As Object,E As Eventargs)

Dim Cnn As OleDbConnection
Dim Cmd As OleDbCommand
Dim StrCnn As String
Dim Sql As String
Dim theTitle As String = title.Text
Dim theQQ As String = QQCode.Text
Dim theHomePage As String = homepage.Text
Dim theContent As String = Content.Text

Dim theLyr As String = Request.Cookies("name").value（这里老提示错误！）
Dim theEmail As String = Request.Cookies("emm").value（这里老提示错误！）

Dim theFace As String = selface.SelectedItem.Value

StrCnn = System.Configuration.ConfigurationSettings.AppSettings("MM_CONNECTION_STRING_Cnn")
Cnn = New OleDbConnection(StrCnn)
Cnn.Open()
Sql = "insert into lyinfo(name,qq,email,homepage,title,content,faceid) values('" & Trim(theLyr) & "','" & Trim(theQQ) & "','" & Trim(theEmail) & "','" & Trim(theHomePage) & "','" & Trim(theTitle) & "','" & Trim(theContent) & "'," & Trim(theFace) & "')"
Cmd = New OleDbCommand(Sql, Cnn)
Cmd.ExecuteNonQuery()
Cnn.Close()
Response.Redirect("lyb.aspx")
end sub

这里的cookie变量我在登录的时候定义的，但到这里想插入数据库就不行了，说什么system.NullReferenceException未将对象引用设置到对象实例，还有什么解决的办法么？？

Answer 1

把Request.Cookies("name").value改为Request.Cookies("name").ToString()试试，如果有数据，应该是数据类型的问题，你前面声明的是string类型，后面也转为string类型。

Answer 2

加上判断 看下Cookies是否是空值 如果不是空值 进行赋值 否则不做操作

Answer 3

这个好像是空值引发的异常。需要IF