我需要让我的程序能够搜索数据库中的每一列，直到找到匹配项，然后将这些匹配项输出到组合框中。我目前已经编写了一种搜索一列（特别是动物名称）的方法，但我需要添加搜索其他列并在组合框中显示多个结果的选项，然后用户可以选择使用程序打开到表格 2，我用来显示数据。
这是我当前正在使用的代码，第一部分用于按动物名称搜索，第二部分用于在可选框中搜索，然后需要将结果显示到组合框中。我还有一个问题，除非名称框中有数据，否则我无法在可选框中搜索，这违背了可选框的目的。任何帮助将不胜感激。
Private Sub btnsear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnsear.Click
If (txtname.Text = "'") Then
MsgBox("No information has been entered")
Else
Try
Dim newsql As String
newsql = "select * from Animals where AnimalName like " & "'%" & txtname.Text & "%'"
'MsgBox("select * from Animals where AnimalName like " & "'" & txtname.Text & "'")
'MsgBox(newsql)
Dim con As New OleDb.OleDbConnection
Dim da As New OleDb.OleDbDataAdapter
'Dim ds As NewDataTable
Dim dt As New DataTable("Animals")
'uses the 2010 compatible connection string
con.ConnectionString = "PROVIDER=Microsoft.ACE.OLEDB.12.0;Data Source = C:\Users\Kamran\Desktop\College\Computing Project\Animals.accdb" 'h:\Animals.accdb"
con.Open()
da = New OleDb.OleDbDataAdapter(newsql, con)
da.Fill(dt)
Form2.Show()
'show name in unbound text box
Form2.nametxt.Text = dt.Rows(0).Item(1)
Form2.latintxt.Text = dt.Rows(0).Item(2)
Form2.locationtxt.Text = dt.Rows(0).Item(3)
Form2.heighttxt.Text = dt.Rows(0).Item(4)
Form2.weighttxt.Text = dt.Rows(0).Item(5)
Form2.diettxt.Text = dt.Rows(0).Item(6)
Form2.statustxt.Text = dt.Rows(0).Item(7)
Form2.lifetxt.Text = dt.Rows(0).Item(8)
Form2.breedtxt.Text = dt.Rows(0).Item(9)
Form2.lengthtxt.Text = dt.Rows(0).Item(10)
Form2.txtimage.Text = dt.Rows(0).Item(11)
Catch
'MsgBox("Animal Not Found")
'con.close()
End Try
End If
If txtname.Text = "" Then
MsgBox("Invalid Search")
Else
Try
Dim newsql As String = "SELECT * FROM Animals WHERE AnimalName LIKE " & "'%" & txtname.Text & "%'"
If txtopt.Text <> "" Then
newsql &= " AND (AnimalName LIKE " & "'%" & txtopt.Text & "%'" & _
" OR LatinName LIKE " & "'%" & txtopt.Text & "%'" & _
" OR Location LIKE " & "'%" & txtopt.Text & "%'" & _
" OR AverageHeight LIKE " & "'%" & txtopt.Text & "%'" & _
" OR AverageWeight LIKE " & "'%" & txtopt.Text & "%'" & _
" OR DietaryNeeds LIKE " & "'%" & txtopt.Text & "%'" & _
" OR ConservationStatus LIKE " & "'%" & txtopt.Text & "%'" & _
" OR AverageLifeSpan LIKE " & "'%" & txtopt.Text & "%'" & _
" OR BreedingSeason LIKE " & "'%" & txtopt.Text & "%'" & _
" OR AverageLength LIKE " & "'%" & txtopt.Text & "%')"
End If
Dim con As New OleDb.OleDbConnection
Dim da As New OleDb.OleDbDataAdapter
Dim dt As New DataTable("Animals")
con.ConnectionString = "PROVIDER=Microsoft.ACE.OLEDB.12.0;Data Source = C:\Users\Kamran\Desktop\College\Computing Project\Animals.accdb" 'h:\Animals.accdb"
con.Open()
da = New OleDb.OleDbDataAdapter(newsql, con)
da.Fill(dt)
Catch
'MsgBox("Item Not Found")
'con.close()
End Try
End If
