PrintDocument:解析索引

Question

请参阅下面的代码。这里的代码将失败：person[i].Pic，因为i是未知的。

如何将索引i传递给PrintPage()-method？

private void BtnPrint_Click(object sender, EventArgs e)
{            
    for (int i = 0; i < persons.Count(); i++)
    {
        PrintDocument pd = new PrintDocument();
        pd.PrintPage += PrintPage;
        pd.Print();
    }
}

private void PrintPage(object o, PrintPageEventArgs e)
{            
    System.Drawing.Image img = System.Drawing.Image.FromFile(person[i].Pic);
    Point loc = new Point(400, 100);
    e.Graphics.DrawImage(img, loc);

}

Answer 1

这样如何：

private void BtnPrint_Click(object sender, EventArgs e)
{            
    for (int i = 0; i < persons.Count(); i++)
    {
        PrintDocument pd = new PrintDocument();

        pd.PrintPage += 
            delegate(object o, PrintPageEventArgs e)
            {            
                var img = System.Drawing.Image.FromFile(person[i].Pic);
                Point loc = new Point(400, 100);
                e.Graphics.DrawImage(img, loc);
            };

        pd.Print();
    }
}

即使用可以访问外部i变量的anonymous method。