datagrid一个通用的DataGridTableStyle的做法



哈，这两天都喜欢写“通用”的东西。

这个类，可以实现自适应列宽、只读、时分显示、事件、任意位置加列、单击单元格背景色设置等等，操作简便。只是时间关系（明天要出去一趟），今天没办法完善。仅供参考，你可以加入别的东西。以下只列代码了，不清楚的自己试用查资料就行了。



Public Class TableStyle



Private m_DataGridTableStyle As DataGridTableStyle

Private m_DataGrid As DataGrid

Private m_DataTable As DataTable

'//添加事件处理，在此只考虑DataGridTextBoxColumn双击事件

Public Delegate Sub ClickEventHandler(ByVal sender As Object, ByVal e As System.EventArgs)

Public Event GridTextBoxDoubleClickEvent As ClickEventHandler

Public Sub GridTextBox_DoubleClick(ByVal sender As Object, ByVal e As System.EventArgs)

RaiseEvent GridTextBoxDoubleClickEvent(sender, e)

End Sub

'//设置DataGrid

Public Property [DataGrid]() As DataGrid

Get

Return m_DataGrid

End Get

Set(ByVal Value As DataGrid)

m_DataGrid = Value

End Set

End Property

'//返回模板

Public ReadOnly Property [DataGridTableStyle]() As DataGridTableStyle

Get

Return m_DataGridTableStyle

End Get

End Property

'//初始化

Public Sub Initialize()

'//判断mDataGrid数据源类型

'//如果绑定的是DataSet或DataViewManager或没有绑定任何数据源，则退出,

If TypeOf m_DataGrid.DataSource Is System.Data.DataSet OrElse _

TypeOf m_DataGrid.DataSource Is System.Data.DataViewManager OrElse _

m_DataGrid.DataSource Is Nothing Then Exit Sub



'//以下分别考虑两种数据源，一是DataView,一是DataTable

If TypeOf m_DataGrid.DataSource Is System.Data.DataView Then

m_DataTable = CType(m_DataGrid.DataSource, DataView).Table

Else

m_DataTable = CType(m_DataGrid.DataSource, DataTable)

End If



m_DataGridTableStyle = New DataGridTableStyle

m_DataGridTableStyle.MappingName = m_DataTable.TableName

'//加ColumnStyle

Dim mDataColumn As DataColumn

Dim mColumnStyle As DataGridColumnStyle

For Each mDataColumn In m_DataTable.Columns



Select Case mDataColumn.DataType.Name

Case "Boolean"

mColumnStyle = New DataGridBoolColumn

Case Else

mColumnStyle = New DataGridTextBoxColumn

AddHandler CType(mColumnStyle, DataGridTextBoxColumn).TextBox.DoubleClick, AddressOf GridTextBox_DoubleClick

End Select



'//绑定到DataTable的Column

With mColumnStyle

.MappingName = mDataColumn.ColumnName

.HeaderText = mDataColumn.ColumnName

End With



'//加入到DataGridTableStyle

m_DataGridTableStyle.GridColumnStyles.Add(mColumnStyle)

Next



'//将DataGridTableStyle绑定到DataGrid

m_DataGrid.TableStyles.Clear()

m_DataGrid.TableStyles.Add(m_DataGridTableStyle)

End Sub

'//自适应宽度

Public Sub AutoExtend()

If m_DataGridTableStyle Is Nothing Then Exit Sub

'取各字段的最大字节数，包括字段名和值

Dim mRow As DataRow

Dim mColumn As DataColumn

For Each mColumn In m_DataTable.Columns

m_DataGridTableStyle.GridColumnStyles(mColumn.ColumnName).Width = GetColumnMaxWidth(0, mColumn.ColumnName)

Next



For Each mRow In m_DataTable.Rows

For Each mColumn In m_DataTable.Columns

If Not IsDBNull(mRow(mColumn.ColumnName)) Then

m_DataGridTableStyle.GridColumnStyles(mColumn.ColumnName).Width = _

GetColumnMaxWidth(m_DataGridTableStyle.GridColumnStyles(mColumn.ColumnName).Width, mRow(mColumn.ColumnName).ToString)

End If

Next

Next



'参照DataGrid的Graphics赋实际宽度

For Each mColumnStyle As DataGridColumnStyle In m_DataGridTableStyle.GridColumnStyles

mColumnStyle.Width = ColumnWidth(mColumnStyle.Width)

Next

End Sub



Private Function GetColumnMaxWidth(ByVal MaxWidth As Integer, ByVal mString As String) As Integer

Dim mLength As Integer

mLength = System.Text.Encoding.Default.GetBytes(mString).Length()

If MaxWidth < mLength Then

Return mLength

Else

Return MaxWidth

End If

End Function

Private Function ColumnWidth(ByVal MaxWidth As Integer) As Integer

Dim mGraphics As Graphics = m_DataGrid.CreateGraphics

Dim mColWidth As Single

mColWidth = mGraphics.MeasureString(New String(CType("A", Char), MaxWidth), m_DataGrid.Font).Width + 2

Return CType(mColWidth, Integer)

End Function

'//在某列后添加一列

Public Sub AddColumn(ByVal PosColumnName As String, ByVal ColumnName As String)

If m_DataGridTableStyle Is Nothing Then Exit Sub

If Not m_DataTable.Columns.Contains(PosColumnName) Then Exit Sub

If m_DataTable.Columns.Contains(ColumnName) Then Exit Sub

Dim tmpStyle As New DataGridTableStyle

For Each mColumnStyle As DataGridColumnStyle In m_DataGridTableStyle.GridColumnStyles

tmpStyle.GridColumnStyles.Add(mColumnStyle)

If mColumnStyle.HeaderText.Equals(PosColumnName) Then

Dim tmpTextColumn As New DataGridTextBoxColumn

m_DataTable.Columns.Add(ColumnName)

tmpTextColumn.HeaderText = ColumnName

tmpTextColumn.MappingName = ColumnName

tmpStyle.GridColumnStyles.Add(tmpTextColumn)

End If

Next

m_DataGrid.TableStyles.Clear()

tmpStyle.MappingName = m_DataGridTableStyle.MappingName

m_DataGridTableStyle = tmpStyle

m_DataGrid.TableStyles.Add(m_DataGridTableStyle)

End Sub

'//不显示NULL

Public WriteOnly Property NotShowNull() As Boolean

Set(ByVal Value As Boolean)

For Each mColumnStyle As DataGridColumnStyle In m_DataGridTableStyle.GridColumnStyles

If Value Then

mColumnStyle.NullText = ""

Else

mColumnStyle.NullText = "(NULL)"

End If

Next

End Set

End Property

'//如果是日期类型，显示时间

Public WriteOnly Property ShowTimeFormat() As Boolean

Set(ByVal Value As Boolean)

For Each mColumnStyle As DataGridColumnStyle In m_DataGridTableStyle.GridColumnStyles

If Not mColumnStyle.MappingName = "" AndAlso m_DataTable.Columns(mColumnStyle.MappingName).DataType.Name.IndexOf("Date") <> -1 Then

If Value Then

CType(mColumnStyle, DataGridTextBoxColumn).Format = "yyyy-MM-dd hh:mm:ss"

Else

CType(mColumnStyle, DataGridTextBoxColumn).Format = "yyyy-MM-dd"

End If

End If

Next

End Set

End Property

'个别编辑,除逻辑类型外

Public ReadOnly Property TextColumnStyle(ByVal ColumnName As String) As DataGridTextBoxColumn

Get

If Not m_DataTable.Columns(ColumnName) Is Nothing AndAlso Not m_DataTable.Columns(ColumnName).DataType.Name.Equals("Boolean") Then

Return CType(m_DataGridTableStyle.GridColumnStyles(ColumnName), DataGridTextBoxColumn)

Else

Return Nothing

End If

End Get

End Property

End Class



'测试

Dim myTableStyle As New TableStyle

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim ds As New DataSet

Me.SqlConnection1.Open()

Me.SqlDataAdapter1.Fill(ds)

Me.SqlConnection1.Close()

Me.DataGrid1.DataSource = ds.Tables(0)
AddHandler myTableStyle.GridTextBoxDoubleClickEvent, AddressOf


End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

With myTableStyle

.DataGrid = Me.DataGrid1

.Initialize()

End With

Me.DataGridTextColumn_DoubleClick

End Sub

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click

myTableStyle.NotShowNull = True

myTableStyle.ShowTimeFormat = True

End Sub



Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click

myTableStyle.NotShowNull = False

myTableStyle.ShowTimeFormat = False

End Sub

Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click

myTableStyle.DataGridTableStyle.GridColumnStyles(2).ReadOnly = True

End Sub



Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click

myTableStyle.AddColumn("姓名", "Hello")

myTableStyle.AutoExtend()

End Sub



Private Sub Button7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click

myTableStyle.TextColumnStyle("姓名").Width=0

End Sub



Private Sub DataGridTextColumn_DoubleClick(ByVal sender As Object, ByVal e As System.EventArgs)

Dim mTextBox As TextBox = CType(sender, TextBox)

mTextBox.BackColor = System.Drawing.Color.Blue

MsgBox(mTextBox.Text)

End Sub