public static int CombineValues <T>(ImmutableArray <T> values, int maxItemsToHash = int.MaxValue)
{
if (values.IsDefaultOrEmpty)
{
return(0);
}
var hashCode = 0;
var count = 0;
foreach (T value in values)
{
if (count++ >= maxItemsToHash)
{
break;
}
// Should end up with a constrained virtual call to object.GetHashCode (i.e. avoid boxing where possible).
if (value != null)
{
hashCode = CodeRefactoringHash.Combine(value.GetHashCode(), hashCode);
}
}
return(hashCode);
}
public static int CombineValues <T>(ImmutableArray <T> values, int maxItemsToHash = int.MaxValue)
{
if (values.IsDefaultOrEmpty)
{
return(0);
}
var hashCode = 0;
var count = 0;
foreach (var value in values)
{
if (count++ >= maxItemsToHash)
{
break;
}
// Should end up with a constrained virtual call to object.GetHashCode (i.e. avoid boxing where possible).
#pragma warning disable RECS0017 // Possible compare of value type with 'null'
if (value != null)
#pragma warning restore RECS0017 // Possible compare of value type with 'null'
{
hashCode = CodeRefactoringHash.Combine(value.GetHashCode(), hashCode);
}
}
return(hashCode);
}
public static int CombineValues <T>(T[] values, int maxItemsToHash = int.MaxValue)
{
if (values == null)
{
return(0);
}
var maxSize = Math.Min(maxItemsToHash, values.Length);
var hashCode = 0;
for (int i = 0; i < maxSize; i++)
{
T value = values[i];
// Should end up with a constrained virtual call to object.GetHashCode (i.e. avoid boxing where possible).
#pragma warning disable RECS0017 // Possible compare of value type with 'null'
if (value != null)
#pragma warning restore RECS0017 // Possible compare of value type with 'null'
{
hashCode = CodeRefactoringHash.Combine(value.GetHashCode(), hashCode);
}
}
return(hashCode);
}
public static int CombineValues(IEnumerable <string> values, StringComparer stringComparer, int maxItemsToHash = int.MaxValue)
{
if (values == null)
{
return(0);
}
var hashCode = 0;
var count = 0;
foreach (var value in values)
{
if (count++ >= maxItemsToHash)
{
break;
}
if (value != null)
{
hashCode = CodeRefactoringHash.Combine(stringComparer.GetHashCode(value), hashCode);
}
}
return(hashCode);
}
/// <summary>
/// Compute the hashcode of a single character using the FNV-1a algorithm
/// See http://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function
/// Note: In general, this isn't any more useful than "char.GetHashCode". However,
/// it may be needed if you need to generate the same hash code as a string or
/// substring with just a single character.
/// </summary>
/// <param name="ch">The character to hash</param>
/// <returns>The FNV-1a hash code of the character.</returns>
public static int GetFNVHashCode(char ch)
{
return(CodeRefactoringHash.CombineFNVHash(CodeRefactoringHash.FnvOffsetBias, ch));
}
