给winform程序附加一个Console程序

在调试winform程序时，经常使用Console类（用来替代Debug类）来写入IDE的输出窗口内容

通过使用kernel32.dll中的AllocConsole（用来附加到winform）函数以及与其匹配的FreeConsole（用来释放）函数让一个Console窗口附加到winform进程中。

这不仅限于调试，还有很多地方经常使用到这种方式

使用的例子：

using System;
using System.Windows.Forms;

namespace FormWithConsole
{
    static class Program
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
#if DEBUG
            NativeMethods.AllocConsole();
            Console.WriteLine("Debug Console");
#endif
            Application.Run(new FormMain());
#if DEBUG
            NativeMethods.FreeConsole();
#endif
        }
    }
}

下面的类包含了附加Console 和释放Console进程的方法

using System;
using System.Runtime.InteropServices;

namespace FormWithConsole
{
    internal static class NativeMethods
    {
        // http://msdn.microsoft.com/en-us/library/ms681944(VS.85).aspx
        /// <summary>
        /// Allocates a new console for the calling process.
        /// </summary>
        /// <returns>nonzero if the function succeeds; otherwise, zero.</returns>
        /// <remarks>
        /// A process can be associated with only one console,
        /// so the function fails if the calling process already has a console.
        /// </remarks>
        [DllImport("kernel32.dll", SetLastError = true)]
        internal static extern int AllocConsole();

        // http://msdn.microsoft.com/en-us/library/ms683150(VS.85).aspx
        /// <summary>
        /// Detaches the calling process from its console.
        /// </summary>
        /// <returns>nonzero if the function succeeds; otherwise, zero.</returns>
        /// <remarks>
        /// If the calling process is not already attached to a console,
        /// the error code returned is ERROR_INVALID_PARAMETER (87).
        /// </remarks>
        [DllImport("kernel32.dll", SetLastError = true)]
        internal static extern int FreeConsole();
    }
}

原文地址：https://www.codeproject.com/Tips/68979/Attaching-a-Console-to-a-WinForms-application

给winform程序附加一个Console程序