C# 弹出确定、取消窗口

if (MessageBox.Show("确定要退出吗？", "", MessageBoxButtons.OKCancel, MessageBoxIcon.Question) == DialogResult.Cancel)
{}

MessageBoxButtons messButton = MessageBoxButtons.OKCancel;
DialogResult dialogResult = MessageBox.Show("是否确定选择Specification Configure文件?", "Configure文件", messButton);
 if (dialogResult == DialogResult.OK)
{}