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Category Archives: C#


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XSD to table generator

http://stackoverflow.com/questions/2628327/how-to-build-a-database-from-an-xsd-schema-and-import-xml-data

http://stackoverflow.com/questions/138575/how-can-i-create-database-tables-from-xsd-files

Creating Database from XSD file

http://stackoverflow.com/questions/403420/convert-xsd-into-sql-relational-tables


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UNC access in C#

Below code helps to access a UNC path with different credentials

Thanks to source article: http://social.msdn.microsoft.com/Forums/en/csharpgeneral/thread/0cbd77b7-5c6c-4a86-bc3a-e06eb888fa17
Usage:
UNCAccess uncAccess = new UNCAccess(uncPath,”username”, “domain”,”Password”);

Code for UNCAccess class:

public class UNCAccess
{
	[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
	internal struct USE_INFO_2
	{
		internal LPWSTR ui2_local;
		internal LPWSTR ui2_remote;
		internal LPWSTR ui2_password;
		internal DWORD ui2_status;
		internal DWORD ui2_asg_type;
		internal DWORD ui2_refcount;
		internal DWORD ui2_usecount;
		internal LPWSTR ui2_username;
		internal LPWSTR ui2_domainname;
	}

	[DllImport("NetApi32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
	internal static extern NET_API_STATUS NetUseAdd(
		LPWSTR UncServerName,
		DWORD Level,
		ref USE_INFO_2 Buf,
		out DWORD ParmError);

	[DllImport("NetApi32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
	internal static extern NET_API_STATUS NetUseDel(
		LPWSTR UncServerName,
		LPWSTR UseName,
		DWORD ForceCond);

	private string sUNCPath;
	private string sUser;
	private string sPassword;
	private string sDomain;
	private int iLastError;
	public UNCAccess()
	{
	}
	public UNCAccess(string UNCPath, string User, string Domain, string Password)
	{
		login(UNCPath, User, Domain, Password);
	}
	public int LastError
	{
		get { return iLastError; }
	}

	///
<summary> /// Connects to a UNC share folder with credentials
 /// </summary>
	///UNC share path
	///Username
	///Domain
	///Password
	/// True if login was successful
	public bool login(string UNCPath, string User, string Domain, string Password)
	{
		sUNCPath = UNCPath;
		sUser = User;
		sPassword = Password;
		sDomain = Domain;
		return NetUseWithCredentials();
	}
	private bool NetUseWithCredentials()
	{
		uint returncode;
		try
		{
			USE_INFO_2 useinfo = new USE_INFO_2();

			useinfo.ui2_remote = sUNCPath;
			useinfo.ui2_username = sUser;
			useinfo.ui2_domainname = sDomain;
			useinfo.ui2_password = sPassword;
			useinfo.ui2_asg_type = 0;
			useinfo.ui2_usecount = 1;
			uint paramErrorIndex;
			returncode = NetUseAdd(null, 2, ref useinfo, out paramErrorIndex);
			iLastError = (int)returncode;
			return returncode == 0;
		}
		catch
		{
			iLastError = Marshal.GetLastWin32Error();
			return false;
		}
	}

	///
<summary> /// Closes the UNC share
 /// </summary>
	/// True if closing was successful
	public bool NetUseDelete()
	{
		uint returncode;
		try
		{
			returncode = NetUseDel(null, sUNCPath, 2);
			iLastError = (int)returncode;
			return (returncode == 0);
		}
		catch
		{
			iLastError = Marshal.GetLastWin32Error();
			return false;
		}
	}

}


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File Helpers to handle large text file

File Helpers to handle large text file

Sample Type
<pre>[Delimitedrecord("|")]
 public class SampleType
 {
	public string Field1;
	public int    Field2;
 }

For small files

FileHelperEngine&lt;SampleType&gt; engine = new FileHelperEngine&lt;SampleType&gt;();
engine.ErrorManager.ErrorMode = ErrorMode.SaveAndContinue;
_dataSet = engine.ReadFile(sourceFilePath).ToDataSet();

For large files
                    FileHelperAsyncEngine engine2 = new FileHelperAsyncEngine(typeof(SampleType));
                    engine2.BeginReadFile(sourceFilePath);

                    List&lt;SampleType&gt; records = new List&lt;SampleType&gt;();
                    int iCount = 0;
                    while (engine2.ReadNext() != null)
                    {
                        records.Add((SampleType)engine2.LastRecord);
                        if (iCount++ &gt; 10000)
                        {
                            //Put in a queue here and call the method to create dataset as follows
                            ///records.ToDataSet();
                            records = new List&lt;SampleType&gt;(); //rinse and repeat till all records are processed.
                        }
                        // put your code here !!!!
                        Console.WriteLine("Data " + records[0].Field1 + " , " + records[0].Field2.ToString());

                    }
Extension method to create Dataset from a list.
 #region Extension Classes
    static class Extensions
    {
        public static DataSet ToDataSet&lt;T&gt;(this IList&lt;T&gt; list)
        {
            Type elementType = typeof(T);
            DataSet ds = new DataSet();
            DataTable t = new DataTable(elementType.Name);
            ds.Tables.Add(t);

            //add a column to table for each public property on T
            foreach (var propInfo in elementType.GetProperties())
            {
                Type ColType = Nullable.GetUnderlyingType(propInfo.PropertyType) ?? propInfo.PropertyType;

                t.Columns.Add(propInfo.Name, ColType);
            }

            //go through each property on T and add each value to the table
            foreach (T item in list)
            {
                DataRow row = t.NewRow();

                foreach (var propInfo in elementType.GetProperties())
                {
                    row[propInfo.Name] = propInfo.GetValue(item, null) ?? DBNull.Value;
                }

                t.Rows.Add(row);
            }

            return ds;
        }
    }
    #endregion


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Paging query helper C#

Code snippet which generates paging query 

int RecordCount = 3435354535647829;
int PageSize = 50000;
int MaxThreadCount = 5;
int PageSizebaseThreadSize = (RecordCount / MaxThreadCount) + 1;

PageSize = PageSizebaseThreadSize;

Console.WriteLine(PageSizebaseThreadSize);

int i = 0;
while(i i = i + PageSize;
}


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Generate XSD for a XML file

Original Link: http://www.gibmonks.com/c_sharp/csharpckbk2-CHP-15-SECT-13.html

[sourceode language=”csharp”]
public static void GenerateSchemaForDirectory(string dir)
{
// Make sure the directory exists.
if (Directory.Exists(dir))
{
// Get the files in the directory.
string[] files = Directory.GetFiles(dir, “*.xml”);
foreach (string file in files)
{
// Set up a reader for the file.
using (XmlReader reader = XmlReader.Create(file))
{
XmlSchemaSet schemaSet = new XmlSchemaSet();
XmlSchemaInference schemaInference =
new XmlSchemaInference();

// Get the schema.
schemaSet = schemaInference.InferSchema(reader);

string schemaPath = “”;
foreach (XmlSchema schema in schemaSet.Schemas())
{
// Make schema file path.
schemaPath = Path.GetDirectoryName(file) + @”\” +
Path.GetFileNameWithoutExtension(file) + “.xsd”;
using (FileStream fs =
new FileStream(schemaPath, FileMode.OpenOrCreate))
{
schema.Write(fs);
}
}
}
}
}
}
[/sourcecode]


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Working with XMLTextReader

Some good articles from MSDN on how to work with XMLTextReader. The below block of code can be used to iterate through the list of book in a XML list of books.

XmlTextReader reader = new XmlTextReader(@"C:\books.xml");

            XmlDocument doc;
            reader.MoveToContent();
            while (reader.Read())
            {
                Application.DoEvents();
                //if (reader.MoveToContent() == XmlNodeType.Element
                 // && reader.Name == "ns0:book")
                if (reader.Name == "ns0:book")
                {
                    doc = new System.Xml.XmlDocument();
                        XmlNode node = doc.ReadNode(reader);
                        txtStatus.Text = txtStatus.Text + node.OuterXml.ToString()
                                        + Environment.NewLine
                                         + "---Processed Node No:"
                                         + i++ + "---" + Environment.NewLine;
                   doc = null;
                }

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, “Courier New”, courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }