Re: Casting to double in C#

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"Aneesh Pulukkul[MCSD.Net]" <aneesh.p@xxxxxxxxx> wrote in message
news:1181317092.656190.3940@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On Jun 8, 8:30 pm, "Aneesh Pulukkul[MCSD.Net]" <anees...@xxxxxxxxx>
wrote:
On Jun 8, 8:18 pm, "Johnny Jörgensen" <j...@xxxxxxxxx> wrote:





What happens if you try

double x = Convert.ToDouble(myReader["TimeStamp"]);

???

Cheers,
Johnny J.

<kanepa...@xxxxxxxxxxx> wrote in message

news:1181314362.001548.67670@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Hi guys, I am having a problem with the following code snippet:-

double x = (myReader["TimeStamp"]);
double y = (myReader["YAxis"]);

Resulting in the follwing compilation error:

Cannot implicitly convert type 'object' to 'double'. An explicit
conversion exists (are you missing a cast?)

To fix this I modified the code to :-

double x = (double)(myReader["TimeStamp"]);
double y = (double)(myReader["YAxis"]);

with this there are no compilation errors but I get a runtime
exception saying :-

System.InvalidCastException: specified cast is not valid.

Any clues on how to fix this will be much appreciated.- Hide quoted
text -

- Show quoted text -

try
{
double x = Double.Parse(myReader["TimeStamp"]);}

catch(....)/Handle exception here. If the string contains data that
cannot be parsed to double it would throw exception.)
{
..........
..........



}- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

Or you can convert the value to string and then parse - better avoid
two conversions.

Cast, not convert, the object to string. There would be only one
conversion, and an explicit cast should be far more efficient than calling
Convert.ToDouble(object) and having a dynamic type check.


.

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