Question

This is my code :

Hashtable actualValues = new Hashtable();
actualValues.Add("Field1", Int32.Parse(field1.Value));
actualValues.Add("Field2", Int32.Parse(field2.Value));
actualValues.Add("Field3", Int32.Parse(field3.Value));

bool isAllZero = true;
foreach (int actualValue in actualValues)
{
    if (actualValue > 1)
        isAllZero = false;
}
if (isAllZero)
{

}

but I get this exception System.InvalidCastException: Specified cast is not valid. on Line 6, close to foreach.

Where am I wrong?

Answer 1

Hashtable returns returns an IEnumerator of type IDictionaryEnumerator, the elements returned by the MoveNext method are of type DictionaryEntry, not int – your foreach loop is invalid.

Try the following:

bool isAllZero = actualValues.Values.Cast<int>().All(v => v == 0);

Or without Linq:

bool isAllZero = true;
foreach (int actualValue in actualValues.Values)
{
  if (actualValue != 0) 
  {
    isAllZero = false;
    break;
  }
}