// This try-finally statement only calls Dispose in the finally block.
Font font1 = new Font("Arial", 10.0f);
try
{
    byte charset = font1.GdiCharSet;
}
finally
{
    if (font1 != null)
    {
        ((IDisposable)font1).Dispose();
    }
}

// You can do the same thing with a using statement.
using (Font font2 = new Font("Arial", 10.0f))
{
    byte charset = font2.GdiCharSet;
}

C#使用using代替try-finally