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Merged
merged 6 commits into from
May 28, 2020
Merged

Add support for standard numeric format strings #788

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456153e
Add support for standard double numeric format strings. Also allow up…
tmilnthorp May 22, 2020
dd720fc
Getting too fancy
tmilnthorp May 22, 2020
043795a
Add abbreviation suffix. Add tests for custom format strings
tmilnthorp May 22, 2020
5e8aea0
Merge branch 'master' into StandardFormatStrings
tmilnthorp May 28, 2020
35e8462
PR requests. Better variable names.
tmilnthorp May 28, 2020
c5c20ef
Add list for valid strings. Update some doc.
tmilnthorp May 28, 2020
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139 changes: 139 additions & 0 deletions UnitsNet.Tests/QuantityFormatterTests.cs
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Original file line number Diff line number Diff line change
@@ -0,0 +1,139 @@
// Licensed under MIT No Attribution, see LICENSE file at the root.
// Copyright 2013 Andreas Gullberg Larsen (andreas.larsen84@gmail.com). Maintained at https://github.com/angularsen/UnitsNet.

using Xunit;

namespace UnitsNet.Tests
{
public class QuantityFormatterTests
{
[Theory]
[InlineData("C")]
[InlineData("C0")]
[InlineData("C1")]
[InlineData("C2")]
[InlineData("C3")]
[InlineData("C4")]
[InlineData("C5")]
[InlineData("C6")]
[InlineData("c")]
[InlineData("c0")]
[InlineData("c1")]
[InlineData("c2")]
[InlineData("c3")]
[InlineData("c4")]
[InlineData("c5")]
[InlineData("c6")]
[InlineData("E")]
[InlineData("E0")]
[InlineData("E1")]
[InlineData("E2")]
[InlineData("E3")]
[InlineData("E4")]
[InlineData("E5")]
[InlineData("E6")]
[InlineData("e")]
[InlineData("e0")]
[InlineData("e1")]
[InlineData("e2")]
[InlineData("e3")]
[InlineData("e4")]
[InlineData("e5")]
[InlineData("e6")]
[InlineData("F")]
[InlineData("F0")]
[InlineData("F1")]
[InlineData("F2")]
[InlineData("F3")]
[InlineData("F4")]
[InlineData("F5")]
[InlineData("F6")]
[InlineData("f")]
[InlineData("f0")]
[InlineData("f1")]
[InlineData("f2")]
[InlineData("f3")]
[InlineData("f4")]
[InlineData("f5")]
[InlineData("f6")]
[InlineData("N")]
[InlineData("N0")]
[InlineData("N1")]
[InlineData("N2")]
[InlineData("N3")]
[InlineData("N4")]
[InlineData("N5")]
[InlineData("N6")]
[InlineData("n")]
[InlineData("n0")]
[InlineData("n1")]
[InlineData("n2")]
[InlineData("n3")]
[InlineData("n4")]
[InlineData("n5")]
[InlineData("n6")]
[InlineData("P")]
[InlineData("P0")]
[InlineData("P1")]
[InlineData("P2")]
[InlineData("P3")]
[InlineData("P4")]
[InlineData("P5")]
[InlineData("P6")]
[InlineData("p")]
[InlineData("p0")]
[InlineData("p1")]
[InlineData("p2")]
[InlineData("p3")]
[InlineData("p4")]
[InlineData("p5")]
[InlineData("p6")]
[InlineData("R")]
[InlineData("R0")]
[InlineData("R1")]
[InlineData("R2")]
[InlineData("R3")]
[InlineData("R4")]
[InlineData("R5")]
[InlineData("R6")]
[InlineData("r")]
[InlineData("r0")]
[InlineData("r1")]
[InlineData("r2")]
[InlineData("r3")]
[InlineData("r4")]
[InlineData("r5")]
[InlineData("r6")]
public static void StandardNumericFormatStrings_Equals_ValueWithFormatStringAndAbbreviation(string format)
{
var length = Length.FromMeters(123456789.987654321);

var expected = string.Format($"{{0:{format}}} {{1:a}}", length.Value, length);
Assert.Equal(expected, QuantityFormatter.Format(length, format));
}

[Theory]
[InlineData("000")]
[InlineData("0.00")]
[InlineData("#####")]
[InlineData("#.##")]
[InlineData("##,#")]
[InlineData("#,#,,")]
[InlineData("%#0.00")]
[InlineData("##.0 %")]
[InlineData("#0.00‰")]
[InlineData("#0.0e0")]
[InlineData("0.0##e+00")]
[InlineData("0.0e+00")]
[InlineData(@"\###00\#")]
[InlineData("#0.0#;(#0.0#);-\0-")]
[InlineData("#0.0#;(#0.0#)")]
public static void CustomNumericFormatStrings_Equals_ValueWithFormatStringAndAbbreviation(string format)
{
var length = Length.FromMeters(123456789.987654321);

var expected = string.Format($"{{0:{format}}} {{1:a}}", length.Value, length);
Assert.Equal(expected, QuantityFormatter.Format(length, format));
}
}
}
188 changes: 149 additions & 39 deletions UnitsNet/QuantityFormatter.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -14,7 +14,66 @@ namespace UnitsNet
public class QuantityFormatter
{
/// <summary>
/// Formats the given quantity using the given format string and format provider.
/// The available UnitsNet custom format specifiers.
/// </summary>
private static readonly char[] UnitsNetFormatSpecifiers = { 'A', 'a', 'G', 'g', 'Q', 'q', 'S', 's', 'U', 'u', 'V', 'v' };

/// <summary>
/// Formats a quantity using the given format string and format provider.
/// </summary>
/// <typeparam name="TUnitType">The quantity's unit type, for example <see cref="LengthUnit"/>.</typeparam>
/// <param name="quantity">The quantity to format.</param>
/// <param name="format">The format string.</param>
/// <remarks>
/// The valid format strings are as follows:
/// <list type="bullet">
/// <item>
/// <term>A standard numeric format string.</term>
/// <description>Any of the standard numeric format for <see cref="IQuantity.Value" /> except for "G" or "g".
/// "C" or "c", "E" or "e", "F" or "f", "N" or "n", "P" or "p", "R" or "r" are all accepted.
/// </description>
/// </item>
/// <item>
/// <term>"G" or "g".</term>
/// <description>The value with 2 significant digits after the radix followed by the unit abbreviation, such as "1.23 m".</description>
/// </item>
/// <item>
/// <term>"A" or "a".</term>
/// <description>The default unit abbreviation for <see cref="IQuantity{TUnitType}.Unit" />, such as "m".</description>
/// </item>
/// <item>
/// <term>"A0", "A1", ..., "An" or "a0", "a1", ..., "an".</term>
/// <description>The n-th unit abbreviation for <see cref="IQuantity{TUnitType}.Unit" />. "a0" is the same as "a".
/// A <see cref="FormatException"/> will be thrown if the requested abbreviation index does not exist.</description>
/// </item>
/// <item>
/// <term>"V" or "v".</term>
/// <description>The string representation of <see cref="IQuantity.Value" /> using the default ToString method.</description>
/// </item>
/// <item>
/// <term>"U" or "u".</term>
/// <description>The enum name of <see cref="IQuantity{TUnitType}.Unit" />, such as "Meter".</description>
/// </item>
/// <item>
/// <term>"Q" or "q".</term>
/// <description>The quantity name, such as "Length".</description>
/// </item>
/// <item>
/// <term>"S1", "S2", ..., "Sn" or "s1", "s2", ..., "sn".</term>
/// <description>The value with n significant digits after the radix followed by the unit abbreviation. For example,
/// "s4" would return "1.2345 m" if <see cref="IQuantity.Value" /> is 1.2345678. Trailing zeros are omitted.</description>
/// </item>
/// </list>
/// </remarks>
/// <returns>The string representation.</returns>
public static string Format<TUnitType>(IQuantity<TUnitType> quantity, string format)
where TUnitType : Enum
{
return Format(quantity, format, CultureInfo.CurrentUICulture);
}

/// <summary>
/// Formats a quantity using the given format string and format provider.
/// </summary>
/// <typeparam name="TUnitType">The quantity's unit type, for example <see cref="LengthUnit"/>.</typeparam>
/// <param name="quantity">The quantity to format.</param>
Expand All @@ -23,57 +82,108 @@ public class QuantityFormatter
/// <see cref="CultureInfo.CurrentUICulture" /> if null.</param>
/// <remarks>
/// The valid format strings are as follows:
/// "g": The value with 2 significant digits after the radix followed by the unit abbreviation, such as "1.23 m".
/// "a": The default unit abbreviation for <see cref="IQuantity{TUnitType}.Unit" />, such as "m".
/// "a0", "a1", ..., "aN": The Nth unit abbreviation for <see cref="IQuantity{TUnitType}.Unit" />. "a0" is the same as "a".
/// A <see cref="FormatException"/> will be thrown if the requested abbreviation index does not exist.
/// "v": String representation of <see cref="IQuantity.Value" />.
/// "u": The enum name of <see cref="IQuantity{TUnitType}.Unit" />, such as "Meter".
/// "q": The quantity name, such as "Length".
/// "s1", "s2", ..., "sN": The value with N significant digits after the radix followed by the unit abbreviation. For example,
/// "s4" would return "1.2345 m" if <see cref="IQuantity.Value" /> is 1.2345678. Trailing zeros are omitted.
/// <list type="bullet">
/// <item>
/// <term>A standard numeric format string.</term>
/// <description>Any of the standard numeric format for <see cref="IQuantity.Value" /> except for "G" or "g".
/// "C" or "c", "E" or "e", "F" or "f", "N" or "n", "P" or "p", "R" or "r" are all accepted.
/// </description>
/// </item>
/// <item>
/// <term>"G" or "g".</term>
/// <description>The value with 2 significant digits after the radix followed by the unit abbreviation, such as "1.23 m".</description>
/// </item>
/// <item>
/// <term>"A" or "a".</term>
/// <description>The default unit abbreviation for <see cref="IQuantity{TUnitType}.Unit" />, such as "m".</description>
/// </item>
/// <item>
/// <term>"A0", "A1", ..., "An" or "a0", "a1", ..., "an".</term>
/// <description>The n-th unit abbreviation for <see cref="IQuantity{TUnitType}.Unit" />. "a0" is the same as "a".
/// A <see cref="FormatException"/> will be thrown if the requested abbreviation index does not exist.</description>
/// </item>
/// <item>
/// <term>"V" or "v".</term>
/// <description>The string representation of <see cref="IQuantity.Value" /> using the default ToString method.</description>
/// </item>
/// <item>
/// <term>"U" or "u".</term>
/// <description>The enum name of <see cref="IQuantity{TUnitType}.Unit" />, such as "Meter".</description>
/// </item>
/// <item>
/// <term>"Q" or "q".</term>
/// <description>The quantity name, such as "Length".</description>
/// </item>
/// <item>
/// <term>"S1", "S2", ..., "Sn" or "s1", "s2", ..., "sn".</term>
/// <description>The value with n significant digits after the radix followed by the unit abbreviation. For example,
/// "s4" would return "1.2345 m" if <see cref="IQuantity.Value" /> is 1.2345678. Trailing zeros are omitted.</description>
/// </item>
/// </list>
/// </remarks>
/// <returns>The string representation.</returns>
public static string Format<TUnitType>(IQuantity<TUnitType> quantity, string format, IFormatProvider? formatProvider)
where TUnitType : Enum
{
formatProvider = formatProvider ?? CultureInfo.CurrentUICulture;
formatProvider ??= CultureInfo.CurrentUICulture;

var number = 0;
var formatString = format;
if(string.IsNullOrWhiteSpace(format))
format = "g";

if(string.IsNullOrEmpty(formatString))
formatString = "g";
char formatSpecifier = format[0];

if(formatString.StartsWith("a") || formatString.StartsWith("s"))
if(UnitsNetFormatSpecifiers.Any(unitsNetFormatSpecifier => unitsNetFormatSpecifier == formatSpecifier))
{
if(formatString.Length > 1 && !int.TryParse(formatString.Substring(1), out number))
throw new FormatException($"The {format} format string is not supported.");
// UnitsNet custom format string

formatString = formatString.Substring(0, 1);
}
int precisionSpecifier = 0;

switch(formatString)
{
case "g":
return ToStringWithSignificantDigitsAfterRadix(quantity, formatProvider, 2);
case "a":
var abbreviations = UnitAbbreviationsCache.Default.GetUnitAbbreviations(quantity.Unit, formatProvider);
switch(formatSpecifier)
{
case 'A':
case 'a':
case 'S':
case 's':
if(format.Length > 1 && !int.TryParse(format.Substring(1), out precisionSpecifier))
throw new FormatException($"The {format} format string is not supported.");
break;
}

switch(formatSpecifier)
{
case 'G':
case 'g':
return ToStringWithSignificantDigitsAfterRadix(quantity, formatProvider, 2);
case 'A':
case 'a':
var abbreviations = UnitAbbreviationsCache.Default.GetUnitAbbreviations(quantity.Unit, formatProvider);

if(precisionSpecifier >= abbreviations.Length)
throw new FormatException($"The {format} format string is invalid because the abbreviation index does not exist.");

if(number >= abbreviations.Length)
throw new FormatException($"The {format} format string is invalid because the abbreviation index does not exist.");
return abbreviations[precisionSpecifier];
case 'V':
case 'v':
return quantity.Value.ToString(formatProvider);
case 'U':
case 'u':
return quantity.Unit.ToString();
case 'Q':
case 'q':
return quantity.QuantityInfo.Name;
case 'S':
case 's':
return ToStringWithSignificantDigitsAfterRadix(quantity, formatProvider, precisionSpecifier);
default:
throw new FormatException($"The {format} format string is not supported.");
}
}
else
{
// Anything else is a standard numeric format string with default unit abbreviation postfix.

return abbreviations[number];
case "v":
return quantity.Value.ToString(formatProvider);
case "u":
return quantity.Unit.ToString();
case "q":
return quantity.QuantityInfo.Name;
case "s":
return ToStringWithSignificantDigitsAfterRadix(quantity, formatProvider, number);
default:
throw new FormatException($"The {format} format string is not supported.");
var abbreviations = UnitAbbreviationsCache.Default.GetUnitAbbreviations(quantity.Unit, formatProvider);
return string.Format(formatProvider, $"{{0:{format}}} {{1}}", quantity.Value, abbreviations.First());
}
}

Expand Down