public int IndexOf(char c, int start, int count)
{
var offset = Offset + start;
if (!HasValue || start < 0 || (uint)offset > (uint)Buffer.Length)
{
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.start);
}
if (count < 0)
{
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.count);
}
var index = Buffer.IndexOf(c, offset, count);
if (index != -1)
{
index -= Offset;
}
return(index);
}
private void ThrowInvalidArguments(int offset, int length)
{
throw GetInvalidArgumentsException(HasValue);
Exception GetInvalidArgumentsException(bool hasValue)
{
if (!hasValue)
{
return(ThrowHelper.GetArgumentOutOfRangeException(ExceptionArgument.offset));
}
if (offset < 0)
{
return(ThrowHelper.GetArgumentOutOfRangeException(ExceptionArgument.offset));
}
if (length < 0)
{
return(ThrowHelper.GetArgumentOutOfRangeException(ExceptionArgument.length));
}
return(ThrowHelper.GetArgumentException(ExceptionResource.Argument_InvalidOffsetLengthStringSegment));
}
}