Question

C#做一个按名称的首字母的模糊查询

比如按下按钮A在dataGridView中就出现所有名字拼音开头为A的人相关的信息。
……
在线等，谢谢
我的数据库里只有名字（汉字），也用字母？
应该不是吧？
那怎么办？
再给每个人名后面加一列汉语拼音吗？

Answer 1

这个我做过， 下面代码实现的是在用户输入一个字母时候，鼠标就定位到以该字母的那一行，如果再按一次还可以定位到下一行。实例是以Name列来演示的。

Private Sub OnGridViewKeyPress(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles DataGridViewProcess.KeyPress
' Get the key char.
Dim pressedChar As Char = Char.ToLower(e.KeyChar)

' Get all the rearch result.
Dim strName As String = String.Empty
For Each dc As DataGridViewColumn In DataGridViewProcess.Columns
If dc.HeaderText.ToLower() = "name" Then
strName = dc.Name
Exit For
End If
Next

' If not find the name column, just return.
If String.IsNullOrEmpty(strName) Then
Exit Sub
End If

Dim searchResult As List(Of DataGridViewRow) = New List(Of DataGridViewRow)
For Each dr As DataGridViewRow In DataGridViewProcess.Rows
If dr.Cells(strName).Value.ToString.ToLower().StartsWith(pressedChar) Then
searchResult.Add(dr)
End If
Next

' Clear all the selected rows
Dim selectedRow As DataGridViewRow = Nothing
Dim findNext As Boolean = False
If DataGridViewProcess.SelectedRows.Count > 0 Then
selectedRow = DataGridViewProcess.SelectedRows(0)
End If
DataGridViewProcess.ClearSelection()

' First, we try to locate the next row after current row.
If selectedRow IsNot Nothing Then
For Each dr As DataGridViewRow In searchResult
If dr.Index > selectedRow.Index Then
findNext = True
dr.Selected = True
DataGridViewProcess.FirstDisplayedScrollingRowIndex = dr.Index
Exit For
End If
Next
End If

' Second, if not find the next row, we try to locate the next row before current row.
If Not findNext Then
For Each dr As DataGridViewRow In searchResult
findNext = True
dr.Selected = True
DataGridViewProcess.FirstDisplayedScrollingRowIndex = dr.Index
Exit For
Next
End If
End Sub

Answer 2

select count(0) from sysobjects where id=object_id(N'表名') and objectproperty(id,N'IsUserTable')=1
如果返回的是0，则不存在，1为存在。

Answer 3

sql语句写成这样就行了：select * from table_name where name like 'A%';

Answer 4

点按钮的时候用SQL在后台做一次模糊检索好了