Question

    public static void WriteLineMultithread(string strt) {
        int lastx=Console.CursorLeft,lasty=Console.CursorTop;

        Console.MoveBufferArea(0,lasty,lastx,1,0,lasty+1,' ',Console.ForegroundColor,Console.BackgroundColor);
        Console.SetCursorPosition(0,lasty);
        Console.WriteLine(strt);
        Console.SetCursorPosition(lastx,lasty+1);
    }

我想让我的程序做的是如果用户选择＆＃34;作者＆＃34;在组合框中，在文本框中写下作者的名字，它将在datagridview中显示结果。我试过这个代码，但不起作用。它总是属于其他声明。

Answer 1

MysqlConn = New MySqlConnection
MysqlConn.ConnectionString = "server=localhost;userid=root;password=**********;database=librarydb;"
Dim SDA As New MySqlDataAdapter
Dim bSource As New BindingSource
Dim dbDataSet As New DataTable
Dim ds As New DataSet
Dim Result As MySqlDataReader
Try
    MysqlConn.Open()
    If ComboBox2.Text = "Author" Then
        Dim Query As String
        Query = "Select quantity as 'Qty',classification as 'Classification',author as 'Author',title as 'Title',call_number as 'Call Number',isbn_number as'ISBN Number' from librarydb.blist where author like'%" & TextBox1.Text & "%'"
        COMMAND = New MySqlCommand(Query, MysqlConn)
        SDA.SelectCommand = COMMAND
        SDA.Fill(dbDataSet)
        Result = COMMAND.ExecuteReader
            If Result.HasRows Then
                 SDA.Fill(dbDataSet)
                 DataGridView1.DataSource = dbDataSet
            Else
                MsgBox("No Datafound") 
            End If
    End If
    MysqlConn.Close()
Catch ex As Exception

End Try

Answer 2

MysqlConn = New MySqlConnection
MysqlConn.ConnectionString = "server=localhost;userid=root;password=**********;database=librarydb;"
Dim SDA As New MySqlDataAdapter
Dim bSource As New BindingSource

Dim dbDataSet As New DataTable

Dim ds As New DataSet
Dim Result As MySqlDataReader
Try
    MysqlConn.Open()
    If ComboBox2.Text = "Author" Then
        Dim Query As String
        Query = "Select quantity as 'Qty',classification as 'Classification',author as 'Author',title as 'Title',call_number as 'Call Number',isbn_number as'ISBN Number' from librarydb.blist where author like'%" & TextBox1.Text & "%'"
        COMMAND = New MySqlCommand(Query, MysqlConn)
        SDA.SelectCommand = COMMAND
        SDA.Fill(dbDataSet)

            If dbDataSet.Rows.count>0 Then
                 DataGridView1.DataSource = dbDataSet
            Else
                MsgBox("No Datafound") 
            End If
    End If
    MysqlConn.Close()
Catch ex As Exception

End Try

如何在Vb.net的消息框中找不到结果？

2 个答案: