The Object cannot be cast from DBNull to other types

Question

List<exchange_rates> exch_rate_list = new List<exchange_rates>();

foreach (DataRow dr in ExchangeRates.Rows) 
{
    exch_rate_list.Add(new exchange_rates {
        one_usd_to_currency = Convert.ToDouble(dr["one_usd_to_currency"]),
        currency =   dr["currency"].ToString(),                       
    });
}

Well I am getting a error saying Object cannot be cast from DBNull to other types at this point one_usd_to_currency = Convert.ToDouble(dr["one_usd_to_currency"]), can someone please guide me on this bug, where i have tried many ways of handling by changing Data Types , i do really appreciate if you could guide me on this bug in order to solve this conflict , many thanks !

Check that `dr["one_usd_to_currency"] != DBNull.Value` before converting it. This is basically the same as a regular NullReferenceException — Rob, Oct 06 '16 at 05:50
You can fix your problem really easy using debug, check how to use it. It will help you in the future ! — mybirthname, Oct 06 '16 at 05:52
Possible duplicate of [Object cannot be cast from DBNull to other types](http://stackoverflow.com/questions/6098646/object-cannot-be-cast-from-dbnull-to-other-types) — MakePeaceGreatAgain, Oct 06 '16 at 05:59

score 2 · Answer 1 · answered Oct 06 '16 at 05:53

2

When you get DBNull as result you have to use this code as DBNull is an own type that cannot be cast to anything different System.Object:

var dbValue = dr["one_usd_to_currency"];
if(dbValue != DBNull.Value) one_usd_to_currency = Convert.ToDouble(dbValue);

answered Oct 06 '16 at 05:53

MakePeaceGreatAgain

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Thank You Very Much ! this line of code helps me to fix this conflict very easily , Many thanks ! – Mirzan Oct 06 '16 at 06:10

score -1 · Answer 2 · edited Oct 06 '16 at 06:04

-1

You can try like....

foreach (DataRow dr in ExchangeRates.Rows) {

    if (dr["one_usd_to_currency"] == null)
        dr["one_usd_to_currency"] = 0;

    exch_rate_list.Add(new exchange_rates {
        one_usd_to_currency = Convert.ToDouble(dr["one_usd_to_currency"]),
        currency =   dr["currency"].ToString(),
    });
}

edited Oct 06 '16 at 06:04

MakePeaceGreatAgain

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answered Oct 06 '16 at 05:56

Sukhvindra Singh

200
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14

The Object cannot be cast from DBNull to other types

2 Answers2