Csharp/C Sharp/Development Class/Trace

Материал из .Net Framework эксперт
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demonstrates post-deployment tracing

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
#define TRACE
/*
  Example21_13.cs demonstrates post-deployment tracing
*/
using System;
using System.Globalization;
using System.Diagnostics;
public class Example21_13 
{
  public static void Main() 
  {
    // Set up a switch to turn tracing on
    BooleanSwitch bsEnableTrace = new BooleanSwitch("TraceOutput", 
      "Turn on tracing");
    // Set up a TraceListener to a file
    TextWriterTraceListener tl = new TextWriterTraceListener("Example21_13.txt");
    Trace.Listeners.Add(tl);
    // And a second TraceListener to the event log
    EventLogTraceListener t2 = new EventLogTraceListener("Application");
    Trace.Listeners.Add(t2);
    Trace.WriteLineIf(bsEnableTrace.Enabled,"Starting Main()");
    // create a date and a currency value
    DateTime dtNow = DateTime.Now;
    Double curOriginal = 12345.67;
    // and format the variables for a specific culture
    CultureInfo ci = new CultureInfo("en-US");
    string sLocalizedDate = dtNow.ToString("d", ci);
    string sLocalizedCur = curOriginal.ToString("c", ci);
    if (bsEnableTrace.Enabled) 
    {
      Trace.Assert(sLocalizedDate != null, "Localized date has no content");
    }
    // print them out
    Console.WriteLine(sLocalizedDate);
    Console.WriteLine(sLocalizedCur);
    Trace.WriteLineIf(bsEnableTrace.Enabled, "Exiting Main()");
    Trace.Flush();
    Trace.Close();
  }
}


demonstrates the use of TraceListener objects

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/

#define DEBUG
/*
  Example21_12.cs demonstrates the use of TraceListener objects
*/
using System;
using System.Globalization;
using System.Diagnostics;
public class Example21_12 
{
  public static void Main() 
  {
    // Set up a TraceListener to a file
    TextWriterTraceListener tl = new TextWriterTraceListener("Example21_12.txt");
    Debug.Listeners.Add(tl);
    // And a second TraceListener to the event log
    EventLogTraceListener t2 = new EventLogTraceListener("Application");
    Debug.Listeners.Add(t2);
    Debug.WriteLine("Starting Main()");
    // create a date and a currency value
    DateTime dtNow = DateTime.Now;
    Double curOriginal = 12345.67;
    // and format the variables for a specific culture
    CultureInfo ci = new CultureInfo("en-US");
    string sLocalizedDate = dtNow.ToString("d", ci);
    string sLocalizedCur = curOriginal.ToString("c", ci);
    Debug.Assert(sLocalizedDate != null, "Localized date has no content");
    // print them out
    Console.WriteLine(sLocalizedDate);
    Console.WriteLine(sLocalizedCur);
    Debug.WriteLine("Exiting Main()");
    Debug.Flush();
    Debug.Close();
  }
}


Trace.WriteLine

 

using System;
using System.Data;
using System.Data.SqlClient;
using System.Threading;
using System.Diagnostics;
class MainClass {
    static void Main() {
        Trace.WriteLine("Entered Main()");
        for (int i = 0; i < 6; i++)
            Trace.WriteLine(i);
        Trace.WriteLine("Exiting from Main()");
    }
}


Use Trace.Fail to alert a fail

 

using System;
using System.Data;
using System.Data.SqlClient;
using System.Threading;
using System.Diagnostics;

class Class1 {
    [STAThread]
    static void Main(string[] args) {
        SqlConnection dbConn = new SqlConnection("server=.;database=pubs;uid=sa;pwd=");
        SqlCommand dbComm = new SqlCommand("SELECT * FROM " + "authors", dbConn);
        SqlDataReader dr = null;
        Trace.WriteLine(DateTime.Now + " - Executing SQL statement");
        try {
            dbConn.Open();
            Trace.Assert(dbConn.State == ConnectionState.Open,"Error", "Connection failed...");
            dr = dbComm.ExecuteReader(CommandBehavior.CloseConnection);
            Trace.Assert(dr != null, "Error","The SqlDataReader is null!");
            while (dr.Read()) {
            }
        } catch {
            Trace.Fail("An error occurred in database access");
        } finally {
            if ((dr.IsClosed == false) && (dr != null))
                dr.Close();
        }
    }
}