At one point I needed to encode a string in hexadecimal representation in order to perform a coding tasks. JavaScript function that does this is:

function encodeToHex(str) {
    var result = "";
    for (var i = 0; i < str.length; i++) {
        result += str.charCodeAt(i).toString(16);
    }
    return result;
}

In some cases we need to inform third parties that a page of ours, or even an entire domain has been moved to another site.

A clear example might be that the domain had www.newagedesign.com and now we’ve moved to www.newagedesign.es. The ideal is to notify everyone that our web address has changed, but this is sometimes not possible or may take a long time. In these cases it is best to redirect the visitor but indicating that redirect because the site has moved.This is achieved by returning a 301 error.

All this said about a domain also applies to a specific page.

For. NET this would be inserting the following code in the page you want to redirect:

Response.Status = "301 Moved Permanently";
Response.AddHeader("Location","http://www.newagedesign.es/");
Response.End();

Function to obtain a URL parameter passed by GET from JavaScript. If the parameter does not exist returns null.

// Helper function to get parameters from the query string.
function getUrlParam(paramName) {
    var reParam = new RegExp('(?:[\?&]|&)' + paramName + '=([^&]+)', 'i');
    var match = window.location.search.match(reParam);
    return (match && match.length > 1) ? match[1] : null;
}

Sometimes we want to serialize an object in JSON, for example when using jQuery AJAX. It’s as easy as this

static public string ToJSON(object obj)
{
    System.Web.Script.Serialization.JavaScriptSerializer serializer = new System.Web.Script.Serialization.JavaScriptSerializer();
    return serializer.Serialize(obj);
}

public static string ChangeImageProportion(string strImgPath, string strImgOutputPath, int iWidth, int iHeight)
{
    try
    {
        //Comprueba la extensión
        //if (Path.GetExtension(strImgPath).ToLower() != ".jpg")
        //{
        //    throw new Exception("El fichero debe estar en formato JPG. (" + strImgPath + ")");
        //}

        //Lee el fichero en un stream
        Stream mystream = null;

        if (strImgPath.StartsWith("http"))
        {
            HttpWebRequest wreq = (HttpWebRequest)WebRequest.Create(strImgPath);
            HttpWebResponse wresp = (HttpWebResponse)wreq.GetResponse();
            mystream = wresp.GetResponseStream();
        }
        else
            mystream = File.OpenRead(strImgPath);

        // Cargo la imágen
        Bitmap source = new Bitmap(mystream);

        int _targetWidth = source.Width;
        int _targetHeight = source.Height;

        /*** Calculo de las proporciones finales ***/
        double _relation = ((double)source.Width) / ((double)source.Height);
        double _canvasRelation = ((double)iWidth) / ((double)iHeight);

        if (_relation > _canvasRelation)
        {
            // El ancho es el lado grande, hay que aumentar el alto
            _targetHeight = iHeight * source.Width / iWidth;
        }
        else if (_relation < _canvasRelation)
        {
            // El alto es el lado grande, hay que aumentar el ancho
            _targetWidth = iWidth * source.Height / iHeight;
        }

        // Ahora miro el desfase
        int iTop = (_targetHeight - source.Height) / 2;
        int iLeft = (_targetWidth - source.Width) / 2;

        // La nueva
        Bitmap target = new Bitmap(_targetWidth, _targetHeight);
        Graphics g = Graphics.FromImage(target);
        g.CompositingQuality = CompositingQuality.HighQuality;

        Color cW = Color.White;
        Brush brush = new SolidBrush(cW);
        g.FillRectangle(brush, 0, 0, _targetWidth, _targetHeight);
        g.DrawImage(source,
                    new Rectangle(iLeft, iTop, source.Width, source.Height),
                    0,
                    0,
                    source.Width,
                    source.Height,
                    GraphicsUnit.Pixel);

        // We will store the correct image codec in this object
        ImageCodecInfo ici = GetEncoderInfo("image/jpeg"); ;
        // This will specify the image quality to the encoder
        EncoderParameter epQuality = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 99L);
        // Store the quality parameter in the list of encoder parameters
        EncoderParameters eps = new EncoderParameters(1);
        eps.Param[0] = epQuality;

        // Genero un nuevo nombre de fichero
        //strImgPath = Path.Combine(Path.GetDirectoryName(strImgPath),Guid.NewGuid().ToString() + ".jpg");

        target.Save(strImgOutputPath, ici, eps);

        source.Dispose();
        target.Dispose();
        g.Dispose();

        return strImgPath;
    }
    catch
    {
        throw;
    }
}

/// <summary>
        /// Obtiene la distancia entre dos coordenadas geográficas
        /// </summary>
        /// <param name="long1InDegrees">Longitud del punto 1 en grados</param>
        /// <param name="lat1InDegrees">Latitud del punto 1 en grados</param>
        /// <param name="long2InDegrees">Longitud del punto 2 en grados</param>
        /// <param name="lat2InDegrees">Latitud del punto 2 en grados</param>
        /// <returns>Distancia entre los dos puntos en metros</returns>
        private static double GetDistance(decimal long1InDegrees, decimal lat1InDegrees, decimal long2InDegrees, decimal lat2InDegrees)
        {
            double lats = (double)(lat1InDegrees - lat2InDegrees);
            double lngs = (double)(long1InDegrees - long2InDegrees);

            //Paso a metros
            double latm = lats * 60 * 1852;
            double lngm = (lngs * Math.Cos((double)lat1InDegrees * Math.PI / 180)) * 60 * 1852;
            double distInMeters = Math.Sqrt(Math.Pow(latm, 2) + Math.Pow(lngm, 2));
            return distInMeters;
        }