public IActionResult RedirectToExternalUrl(string shortUrl)
{
// Verify that this Url is in the database
string originalUrl = AzureTable.GetOriginalUrl(shortUrl);
// If the shorten is correct
// Increment the number of hits for this shorten
// And redirect the user to the original Url
if (originalUrl == null)
{
return(Redirect("api/error"));
}
else
{
AzureTable.IncrementHit(shortUrl);
return(Redirect(originalUrl));
}
}
public static string Create(string originalURL)
{
// List of possible character for the shorten
List <string> alphaNum = new List <string>()
{
"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p",
"q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "A", "B", "C", "D", "E", "F",
"G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V",
"W", "X", "Y", "Z", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9"
};
// Transform indice (base 10) to base 62
ulong idUrl = AzureTable.GetIndice();
int r = (int)(idUrl % 62);
ulong q = idUrl / 62;
string shortUrl = alphaNum[r];
int l = 1;
while (q > 62)
{
q = q / 62;
r = (int)(q % 62);
shortUrl += alphaNum[r];
l += 1;
}
shortUrl += alphaNum[(int)q];
for (int i = l; i <= 7; i++)
{
shortUrl += alphaNum[0];
}
// Store in database
AzureTable.InsertUrlDrawer(new UrlDrawer(originalURL, shortUrl));
return(shortUrl);
}