//Import System.IO in your application for StreamWriter Object

//note: excel_file represents the complete physical address of excel file eg  C:/myexcel.xls
public  void export_datagridview_to_excel(DataGridView dgv, string excel_file)
{
int cols;
//open file
StreamWriter wr = new StreamWriter(excel_file);

//determine the number of columns and write columns to file
cols = dgv.Columns.Count;
for (int i = 0; i < cols; i++)
{
wr.Write(dgv.Columns[i].Name.ToString().ToUpper() + “\t”);
}

wr.WriteLine();

//write rows to excel file
for (int i = 0; i < (dgv.Rows.Count - 1); i++)
{
for (int j = 0; j < cols; j++)
{
if (dgv.RowsIdea.Cells[j].Value != null)
wr.Write(dgv.Rows[i].Cells[j].Value + “\t”);
else
{
wr.Write(”\t”);
}
}

wr.WriteLine();
}

//close file
wr.Close();
}

object.ToString ( "Fn" );

where F is a single alphabetic character called the format specifier, and n can be one or more digits called the precision specifier.

The following table describes the standard numeric format strings. Note that the patterns produced by these format specifiers are influenced by the settings in the Regional Options control panel. Computers using different cultures or different currency settings will display different patterns.

“Label2 does not exist in the current context”

So I found that the problem was even though I renamed one of my old files it still contained the class that my codebehind was referencing (i.e. the class names were still the same) – and therefore was not seeing the newly added Label control to my new code.Shame the compiler doesn’t realise the duplication and give some indication.

Lesson: Remove any backed up files from the web folder and/or build directory to avoid pain

        public string GetMD5Hash(string input)
        {
            System.Security.Cryptography.MD5CryptoServiceProvider x = new System.Security.Cryptography.MD5CryptoServiceProvider();
            byte[] bs = System.Text.Encoding.UTF8.GetBytes(input);
            bs = x.ComputeHash(bs);
            System.Text.StringBuilder s = new System.Text.StringBuilder();
            foreach (byte b in bs)
            {
                s.Append(b.ToString("x2").ToLower());
            }
            string password = s.ToString();
            return password;
        }

And this one is in PHP

These both will return the same value

SPWeb web = SPContext.Current.Web.Site.OpenWeb();
SPUser user = web.AllUsers[username];
SPUserToken userToken = user.UserToken;
SPSite site = new SPSite(SPContext.Current.Web.Site.Url.ToString(), userToken);
web = site.OpenWeb();

Here username is the name username of the user who you want to impersonate as.

Hope this helps

 private  void processTextbox()
{
     foreach (Control ctrl in Page.Controls)
     {
          if (ctrl is TextBox)
          {
              //do something here
          }
          else
          {
              //do something here
          }
     }
}

Njoy coding

public void ConvertImage2Jpeg(string input, string output)
{
try
{
ImageCodecInfo myimagecodeinfo;
string inputpath;
string outputpath = output;
string format;
inputpath = input;
format = inputpath.Substring(inputpath.LastIndexOf(".") + 1);

if (format == "tif")
{
myimagecodeinfo = GetEncoderInfo("image/tiff");

}
else
{
myimagecodeinfo = GetEncoderInfo("image/" + format);

}
EncoderParameters eparam = new EncoderParameters(1);
EncoderParameter encparam;
System.Drawing.Imaging.Encoder enc;
enc = System.Drawing.Imaging.Encoder.Transformation;
encparam = new EncoderParameter(enc, (long)EncoderValue.TransformRotate90);
eparam.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 10L);
string jpg;
Image img;
img = Image.FromFile(inputpath);
jpg = outputpath.Substring(0, outputpath.LastIndexOf("\\") + 1) + Path.GetFileNameWithoutExtension(inputpath) + ".JPG";
img.Save(jpg, myimagecodeinfo, eparam);

}
catch (Exception exp)
{

}

}

private static ImageCodecInfo GetEncoderInfo(String mimeType)
{
int j;
ImageCodecInfo[] encoders;
encoders = ImageCodecInfo.GetImageEncoders();
for (j = 0; j < encoders.Length; ++j)
{
if (encoders[j].MimeType == mimeType)
return encoders[j];
}
return null;
}

On googling, I found after doing this you can make your text box read only and also it will return the value of the text box. You need to insert this line on your Page_Load

TextBox1.Attributes.Add(“readonly”, “true”);

You can download some of the code snippets from http://msdn.microsoft.com/en-us/vstudio/aa718338.aspx all you need to do is install this file at “My Documents\Visual Studio 2008\Code Snippets\Visual C#\My Code Snippets” location. You can also find some more snippets at http://www.codeplex.com/snippetlibcsharp/Release/ProjectReleases.aspx?ReleaseId=14841 all you need to do is copy this snippet at “My Documents\Visual Studio 2008\Code Snippets\Visual C#\My Code Snippets” and you are ready to use these ready made code into your visual studio using shortcuts “ctrl k + ctrl x”

You can also insert the snippets by writing a part of it and pressing tab twice. For e.g. to insert a new property in your code type

prop + tab + tab

this will insert a property in your code window.

So keep using this to improve your productivity, and enjoy coding.

:Ajay Matharu