convert to double is not working

Question

User1052662409 posted

Hi

I am converting a long type to double for satisfying a condition, but it is not working.

foreach (S3Object entry in response.S3Objects)
          {
            if (Stringcl.GetValue(entry.Key).ToLower().Contains("signed release") && Stringcl.GetValue(entry.Key).ToLower().Contains(".pdf"))
            {
              if (Convert.ToDouble(entry.Size / 1024 / 1024) > 3.5)
              {
                oUtilcl.LogMessage("File size is greater than 3.5 MB");
                return "File size is greater than 3.5 MB";
              }
              else
              {
 // always goes in this block
}

I am converting the entry.Size into MB (as it is in bytes) if (Convert.ToDouble(entry.Size / 1024 / 1024) > 3.5) and the value of [entry.Size / 1024 / 1024] = 3.62 but still it goes into else block.

Why?

Answer 1

User475983607 posted

I am converting the entry.Size into MB (as it is in bytes) if (Convert.ToDouble(entry.Size / 1024 / 1024) > 3.5) and the value of [entry.Size / 1024 / 1024] = 3.62 but still it goes into else block.

Why?

Simply, the division is done before the Convert.ToDouble method is invoked and the math produces an integer.  Try this...

if (Convert.ToDouble((double)entry.Size / 1024d / 1024d) > 3.5d)

Answer 2

User753101303 posted

Hi,

You are working with integers so you produce an integer that you then convert to a double. You should convert the size and then do the calculation. For example try a console app such as :

static void Main(string[] args)
{
   int size = 3795845;
   Console.WriteLine(Convert.ToDouble(size / 1024 / 1024)); // 3
   Console.WriteLine(Convert.ToDouble(size) / 1024 / 1024); // around 3.62
}