如何使用MySQL将项目添加到列表框
我试图将所有行中的标题()添加到列表框中,但出现以下错误: System.Data.dll中发生类型为“System.IndexOutOfRangeException”的未处理异常。我不知道现在该怎么做,我已经尝试添加函数,使其成为名为item的变量如何使用MySQL将项目添加到列表框,mysql,vb.net,listbox,Mysql,Vb.net,Listbox,我试图将所有行中的标题()添加到列表框中,但出现以下错误: System.Data.dll中发生类型为“System.IndexOutOfRangeException”的未处理异常。我不知道现在该怎么做,我已经尝试添加函数,使其成为名为item的变量 Public Function updatenews() Dim MySqlConnection As New MySqlConnection() Dim newsmydatatable As New DataTable D
Public Function updatenews()
Dim MySqlConnection As New MySqlConnection()
Dim newsmydatatable As New DataTable
Dim rowcount As Integer = 0
Dim amount As Integer
MySqlConnection.ConnectionString = "server=" + host + "; user id=" + user + "; password=" + password + "; database=website;"
Try
MySqlConnection.Open()
Catch myerror As MySqlException
MessageBox.Show("Cannot connect news server: " & myerror.Message & "Please check your internet connection settings and try again. If problem persists contact support.")
Label3.Text = "Error!"
End Try
Dim myadapter As New MySqlDataAdapter
Dim newsmydatatable As New DataTable
Dim sqlquary = "SELECT * FROM news;"
Dim command As New MySqlCommand
command.Connection = MySqlConnection
command.CommandText = sqlquary
myadapter.SelectCommand = command
myadapter.Fill(newsmydatatable)
Dim mydata As MySqlDataReader
mydata = command.ExecuteReader()
If mydata.HasRows = 0 Then
Else
amount = newsmydatatable.Rows.Count
MsgBox(amount)
For value As Integer = 0 To amount
For value As Integer = 0 To amount
ListBox1.Items.Add(newsmydatatable.Rows(rowcount).Item("title"))
rowcount += 1
Next
End If
End Function
如果您有:
ListBox1.Items.Add(newsmydatatable.Rows(rowcount).Item("title"))
rowcount += 1
将其更改为:
ListBox1.Items.Add(newsmydatatable.Rows(value).Item("title"))
“else”中的代码看起来有点乱七八糟-可能是在编辑中-但看起来你已经爱上了那颗老栗子-如果rows.count是10,那么它们的编号是从0到9Awh,谢谢!刚刚将0更改为`现在可以工作了!谢谢并删除两个for循环,您只需要一个:)