Protected MyBtn As Button
Protected Sub FpSpread1_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles FpSpread1.Init
　　MyBtn = New Button
　　MyBtn.Width = Unit.Pixel(20)
　　MyBtn.Height = Unit.Pixel(20)
　　MyBtn.BackColor = Drawing.Color.Red

　　MyBtn.CommandName = "ping"
　　Dim sarg As String = "javascript:" + FpSpread1.ClientID + ".CallBack('ping');return false;"
　　MyBtn.Attributes.Add("onclick", sarg)
End Sub

Protected Sub FpSpread1_PreRender(ByVal sender As Object, ByVal e As System.EventArgs) Handles FpSpread1.PreRender
　　'Dim con As Control = FpSpread1.FindControl("Copy") 'SP3以前の実装方法
　　Dim con As Control = FpSpread1.FindControl(String.Format("{0}_{1}", FpSpread1.ClientID, "Copy")) 'SP4以降の実装方法

　　Dim tc As TableCell = CType(con.Parent, TableCell)
　　Dim tr As TableRow = CType(tc.Parent, TableRow)

　　Dim c As New TableCell
　　c.Controls.Add(MyBtn)

　　tr.Cells.Add(c)
End Sub

Protected Sub MyBtn_Command(ByVal sender As Object, ByVal e As FarPoint.Web.Spread.SpreadCommandEventArgs) Handles FpSpread1.ButtonCommand
　　If e.CommandName = "ping" Then
　　　　FpSpread1.Sheets(0).Cells(0, 0).Text += "Clicked"
　　End If
End Sub

Button MyBtn;
protected void FpSpread1_Init(object sender, EventArgs e)
{
　　MyBtn = new Button();
　　MyBtn.Width = Unit.Pixel(20);
　　MyBtn.Height = Unit.Pixel(20);
　　MyBtn.BackColor = System.Drawing.Color.Red;
　　MyBtn.CommandName = "ping";

　　string sarg = "javascript:" + FpSpread1.ClientID + ".CallBack('ping');return false;";
　　MyBtn.Attributes.Add("onclick", sarg);

　　// SPREADのイベントを登録
　　FpSpread1.ButtonCommand += new FarPoint.Web.Spread.SpreadCommandEventHandler(FpSpread1_ButtonCommand);
}

protected void FpSpread1_PreRender(object sender, EventArgs e)
{
　　//Control con = FpSpread1.FindControl("Copy"); //SP3以前の実装方法
　　Control con = FpSpread1.FindControl(string.Format("{0}_{1}", FpSpread1.ClientID, "Copy")); //SP4以降の実装方法
　　TableCell tc = ((TableCell)(con.Parent));
　　TableRow tr = ((TableRow)(tc.Parent));
　　TableCell c = new TableCell();

　　c.Controls.Add(MyBtn);
　　tr.Cells.Add(c);
}

protected void FpSpread1_ButtonCommand(object sender, FarPoint.Web.Spread.SpreadCommandEventArgs e)
{
　　if ((e.CommandName == "ping"))
　　{
　　　　FpSpread1.Sheets[0].Cells[0, 0].Text += "Clicked";
　　}
}