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C# FormattingData.TryWriteDigitOrSymbol方法代碼示例

本文整理匯總了C#中System.Text.Formatting.FormattingData.TryWriteDigitOrSymbol方法的典型用法代碼示例。如果您正苦於以下問題:C# FormattingData.TryWriteDigitOrSymbol方法的具體用法?C# FormattingData.TryWriteDigitOrSymbol怎麽用?C# FormattingData.TryWriteDigitOrSymbol使用的例子?那麽, 這裏精選的方法代碼示例或許可以為您提供幫助。您也可以進一步了解該方法所在System.Text.Formatting.FormattingData的用法示例。


在下文中一共展示了FormattingData.TryWriteDigitOrSymbol方法的1個代碼示例,這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚,您的評價將有助於係統推薦出更棒的C#代碼示例。

示例1: TryFormatDecimal

        // TODO: this whole routine is too slow. It does div and mod twice, which are both costly (especially that some JITs cannot optimize it).
        // It does it twice to avoid reversing the formatted buffer, which can be tricky given it should handle arbitrary cultures.
        // One optimization I thought we could do is to do div/mod once and store digits in a temp buffer (but that would allocate). Modification to the idea would be to store the digits in a local struct
        // Another idea possibly worth tying would be to special case cultures that have constant digit size, and go back to the format + reverse buffer approach.
        private static bool TryFormatDecimal(ulong value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
        {
            if(format.IsDefault)
            {
                format.Symbol = 'G';
            }
            format.Symbol = Char.ToUpperInvariant(format.Symbol); // TODO: this is costly. I think the transformation should happen in Parse
            Precondition.Require(format.Symbol == 'D' || format.Symbol == 'G' || format.Symbol == 'N');

            // Reverse value on decimal basis, count digits and trailing zeros before the decimal separator
            ulong reversedValueExceptFirst = 0;
            var digitsCount = 1;
            var trailingZerosCount = 0;

            // We reverse the digits in numeric form because reversing encoded digits is hard and/or costly.
            // If value contains 20 digits, its reversed value will not fit into ulong size.
            // So reverse it till last digit (reversedValueExceptFirst will have all the digits except the first one).
            while (value >= 10)
            {
                var digit = value % 10UL;
                value = value / 10UL;

                if (reversedValueExceptFirst == 0 && digit == 0)
                {
                    trailingZerosCount++;
                }
                else
                {
                    reversedValueExceptFirst = reversedValueExceptFirst * 10UL + digit;
                    digitsCount++;
                }
            }

            bytesWritten = 0;
            int digitBytes;
            // If format is D and precision is greater than digitsCount + trailingZerosCount, append leading zeros
            if (format.Symbol == 'D' && format.HasPrecision)
            {
                var leadingZerosCount = format.Precision - digitsCount - trailingZerosCount;
                while (leadingZerosCount-- > 0)
                {
                    if (!formattingData.TryWriteDigitOrSymbol(0, buffer.Slice(bytesWritten), out digitBytes))
                    {
                        bytesWritten = 0;
                        return false;
                    }
                    bytesWritten += digitBytes;
                }
            }

            // Append first digit
            if (!formattingData.TryWriteDigit(value, buffer.Slice(bytesWritten), out digitBytes))
            {
                bytesWritten = 0;
                return false;
            }
            bytesWritten += digitBytes;
            digitsCount--;

            if (format.Symbol == 'N')
            {
                const int GroupSize = 3;

                // Count amount of digits before first group separator. It will be reset to groupSize every time digitsLeftInGroup == zero
                var digitsLeftInGroup = (digitsCount + trailingZerosCount) % GroupSize;
                if (digitsLeftInGroup == 0)
                {
                    if (digitsCount + trailingZerosCount > 0)
                    {
                        // There is a new group immediately after the first digit
                        if (!formattingData.TryWriteSymbol(FormattingData.Symbol.GroupSeparator, buffer.Slice(bytesWritten), out digitBytes))
                        {
                            bytesWritten = 0;
                            return false;
                        }
                        bytesWritten += digitBytes;
                    }
                    digitsLeftInGroup = GroupSize;
                }

                // Append digits
                while (reversedValueExceptFirst > 0)
                {
                    if (digitsLeftInGroup == 0)
                    {
                        if (!formattingData.TryWriteSymbol(FormattingData.Symbol.GroupSeparator, buffer.Slice(bytesWritten), out digitBytes))
                        {
                            bytesWritten = 0;
                            return false;
                        }
                        bytesWritten += digitBytes;
                        digitsLeftInGroup = GroupSize;
                    }

                    var nextDigit = reversedValueExceptFirst % 10UL;
                    reversedValueExceptFirst = reversedValueExceptFirst / 10UL;
//.........這裏部分代碼省略.........
開發者ID:TerabyteX,項目名稱:corefxlab,代碼行數:101,代碼來源:IntegerFormatter.cs


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