在WPF中,使用控制檯輸出日誌資訊
阿新 • • 發佈:2019-01-23
一、背景
之前的專案中,使用Log4NET將日誌資訊輸出到文字檔案中。這種方法適用於常看以前的日誌資訊,卻並不適用於實時檢視日誌。本以為Log4NET可以很方便地通過配置appender來解決這個問題。無奈,個人水平有限,只能夠在控制檯程式中實現,而在WPF應用中沒有解決這個問題。後來將解決方案轉win32。通過呼叫win32函式來直接輸出資訊到控制檯。
二、解決方案
幫助類
public class ConsoleLogHelper
{
[System.Security.SuppressUnmanagedCodeSecurity]
[DllImport("kernel32" , CharSet = CharSet.Auto)]
internal static extern bool AllocConsole();
[System.Security.SuppressUnmanagedCodeSecurity]
[DllImport("kernel32", CharSet = CharSet.Auto)]
internal static extern bool FreeConsole();
/// <summary>
/// 在程式啟動時,執行一次即可
/// </summary>
public static void OpenConsole()
{
try
{
var consoleTitle = "App Runtime Log";
AllocConsole();
Console.BackgroundColor = ConsoleColor.Black;
Console.CursorVisible = false;
Console.Title = consoleTitle;
}
catch (Exception)
{
throw;
}
}
/// <summary>
/// 該方法只在退出程式時,呼叫
/// </summary>
public static void CloseConsole()
{
FreeConsole();
}
public static void WriteLine(string msg)
{
Console.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));
Console.WriteLine(msg);
Console.ForegroundColor = ConsoleColor.White;
}
public static void WriteLineError(string msg)
{
Console.ForegroundColor = ConsoleColor.Red;
WriteLine(msg);
}
public static void WriteLineError(Exception ex)
{
WriteLineError(ex.Message);
}
public static void WriteLineInfo(string msg)
{
Console.ForegroundColor = ConsoleColor.Cyan;
WriteLine(msg);
}
}
使用 App.cs
public partial class App : Application
{
protected override void OnStartup(StartupEventArgs e)
{
base.OnStartup(e);
ConsoleLogHelper.OpenConsole();
}
protected override void OnExit(ExitEventArgs e)
{
base.OnExit(e);
ConsoleLogHelper.CloseConsole();
}
}
使用 MainWindow.xaml
<Window x:Class="Log4Net_Appender_Console.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:Log4Net_Appender_Console"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Grid>
<StackPanel>
<Button Click="Button_Click_default"
Width="200"
Height="50">default</Button>
<Button Click="Button_Click_error"
Width="200"
Height="50">error</Button>
<Button Click="Button_Click_exception"
Width="200"
Height="50">exception</Button>
<Button Click="Button_Click_info"
Width="200"
Height="50">info</Button>
</StackPanel>
</Grid>
</Window>
使用 MainWindow.cs
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void Excute(Action<int> action)
{
for (int i = 0; i < 10; i++)
{
action(i);
}
}
private void Button_Click_default(object sender, RoutedEventArgs e)
{
Excute((i)=> {
Console.WriteLine($"default-->{i.ToString()}");
});
}
private void Button_Click_error(object sender, RoutedEventArgs e)
{
Excute((i) => {
ConsoleLogHelper.WriteLineError($"error-->{i.ToString()}");
});
}
private void Button_Click_exception(object sender, RoutedEventArgs e)
{
try
{
string a = null;
a.ToString();
}
catch (Exception ex)
{
Excute((i) => {
ConsoleLogHelper.WriteLineError(ex);
});
}
}
private void Button_Click_info(object sender, RoutedEventArgs e)
{
Excute((i) => {
ConsoleLogHelper.WriteLineInfo($"info-->{i.ToString()}");
});
}
}
三、分析
使用核心函式AllocConsole()在當前執行緒中開啟一個控制檯。然後使用Console.WriteLine()將資訊輸出到控制檯。