public void Chaining_Dictionary()
{
var dict = new System.Collections.Generic.Dictionary <int, int> {
[1] = 2, [3] = 4
};
var sortedDict = new System.Collections.Generic.SortedDictionary <int, int> {
[1] = 2, [3] = 4
};
System.Collections.Generic.KeyValuePair <int, int> dictKvp = default(System.Collections.Generic.KeyValuePair <int, int>);
foreach (var kv in dict)
{
dictKvp = kv;
break;
}
System.Collections.Generic.KeyValuePair <int, int> sortedDictKvp = default(System.Collections.Generic.KeyValuePair <int, int>);
foreach (var kv in sortedDict)
{
sortedDictKvp = kv;
break;
}
Assert.AreEqual(dictKvp, dict.First());
Assert.AreEqual(dictKvp, dict.First(x => true));
Assert.AreEqual(dictKvp, dict.FirstOrDefault());
Assert.AreEqual(dictKvp, dict.FirstOrDefault(x => true));
Assert.AreEqual(sortedDictKvp, sortedDict.First());
Assert.AreEqual(sortedDictKvp, sortedDict.First(x => true));
Assert.AreEqual(sortedDictKvp, sortedDict.FirstOrDefault());
Assert.AreEqual(sortedDictKvp, sortedDict.FirstOrDefault(x => true));
}
public void Errors_Dictionary()
{
var dict = new System.Collections.Generic.Dictionary <int, int> {
[1] = 2, [3] = 4
};
var sortedDict = new System.Collections.Generic.SortedDictionary <int, int> {
[1] = 2, [3] = 4
};
try { dict.First(null); Assert.Fail(); }catch (ArgumentNullException exc) { Assert.AreEqual("predicate", exc.ParamName); }
try { dict.FirstOrDefault(null); Assert.Fail(); } catch (ArgumentNullException exc) { Assert.AreEqual("predicate", exc.ParamName); }
try { sortedDict.First(null); Assert.Fail(); } catch (ArgumentNullException exc) { Assert.AreEqual("predicate", exc.ParamName); }
try { sortedDict.FirstOrDefault(null); Assert.Fail(); } catch (ArgumentNullException exc) { Assert.AreEqual("predicate", exc.ParamName); }
}