Fix output of complex number formatting (#46235)

gewarren · web-flow · commit c0a7d4954fa2 · 2025-05-17T21:43:49.000-07:00
* fix output of complex number formatting

* break long lines
diff --git a/docs/core/compatibility/core-libraries/8.0/complex-format.md b/docs/core/compatibility/core-libraries/8.0/complex-format.md
@@ -36,3 +36,7 @@ If you need the previous format, you can use a custom string formatting mechanis
 ## Affected APIs
 
 - <xref:System.Numerics.Complex.ToString%2A?displayProperty=fullName>
+
+## See also
+
+- [Format a complex number](../../../../fundamentals/runtime-libraries/system-numerics-complex.md#format-a-complex-number)
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/Program.cs b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/Program.cs
@@ -0,0 +1 @@
+﻿CustomFormatEx.Run();
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/Project.csproj b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/Project.csproj
@@ -1,8 +1,8 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <OutputType>Library</OutputType>
-    <TargetFrameworks>net8</TargetFrameworks>
+    <OutputType>Exe</OutputType>
+    <TargetFrameworks>net9</TargetFrameworks>
   </PropertyGroup>
 
  </Project>
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/create1.cs b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/create1.cs
@@ -4,7 +4,7 @@
 
 public class CreateEx
 {
-    public static void Main()
+    public static void Run()
     {
         // Create a complex number by calling its class constructor.
         Complex c1 = new Complex(12, 6);
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/customfmt1.cs b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/customfmt1.cs
@@ -15,17 +15,16 @@ public object GetFormat(Type formatType)
     public string Format(string format, object arg,
                          IFormatProvider provider)
     {
-        if (arg is Complex)
+        if (arg is Complex c1)
         {
-            Complex c1 = (Complex)arg;
             // Check if the format string has a precision specifier.
             int precision;
-            string fmtString = String.Empty;
+            string fmtString = string.Empty;
             if (format.Length > 1)
             {
                 try
                 {
-                    precision = Int32.Parse(format.Substring(1));
+                    precision = int.Parse(format.Substring(1));
                 }
                 catch (FormatException)
                 {
@@ -42,12 +41,12 @@ public string Format(string format, object arg,
         }
         else
         {
-            if (arg is IFormattable)
-                return ((IFormattable)arg).ToString(format, provider);
+            if (arg is IFormattable formattable)
+                return formattable.ToString(format, provider);
             else if (arg != null)
                 return arg.ToString();
             else
-                return String.Empty;
+                return string.Empty;
         }
     }
 }
@@ -56,22 +55,21 @@ public string Format(string format, object arg,
 // <Snippet4>
 public class CustomFormatEx
 {
-    public static void Main()
+    public static void Run()
     {
-        Complex c1 = new Complex(12.1, 15.4);
-        Console.WriteLine("Formatting with ToString():       " +
-                          c1.ToString());
-        Console.WriteLine("Formatting with ToString(format): " +
-                          c1.ToString("N2"));
-        Console.WriteLine("Custom formatting with I0:        " +
-                          String.Format(new ComplexFormatter(), "{0:I0}", c1));
-        Console.WriteLine("Custom formatting with J3:        " +
-                          String.Format(new ComplexFormatter(), "{0:J3}", c1));
+        Complex c1 = new(12.1, 15.4);
+        Console.WriteLine($"Formatting with ToString:         {c1}");
+        Console.WriteLine($"Formatting with ToString(format): {c1:N2}");
+        Console.WriteLine($"Custom formatting with I0:\t" +
+            $"  {string.Format(new ComplexFormatter(), "{0:I0}", c1)}");
+        Console.WriteLine($"Custom formatting with J3:\t" +
+            $"  {string.Format(new ComplexFormatter(), "{0:J3}", c1)}");
     }
 }
+
 // The example displays the following output:
-//    Formatting with ToString():       (12.1, 15.4)
-//    Formatting with ToString(format): (12.10, 15.40)
+//    Formatting with ToString():       <12.1; 15.4>
+//    Formatting with ToString(format): <12.10; 15.40>
 //    Custom formatting with I0:        12 + 15i
 //    Custom formatting with J3:        12.100 + 15.400j
 // </Snippet4>
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/nan1.cs b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/nan1.cs
@@ -4,7 +4,7 @@
 
 public class NaNEx
 {
-    public static void Main()
+    public static void Run()
     {
         Complex c1 = new Complex(Double.MaxValue / 2, Double.MaxValue / 2);
 
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/precision1.cs b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/csharp/precision1.cs
@@ -1,9 +1,9 @@
-using System;
+﻿using System;
 using System.Numerics;
 
 public class PrecisionEx
 {
-    public static void Main()
+    public static void Run()
     {
         // <Snippet5>
         Complex value = new Complex(Double.MinValue / 2, Double.MinValue / 2);
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/Program.vb b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/Program.vb
@@ -0,0 +1,5 @@
+﻿Public Class Program
+    Public Shared Sub Main()
+        Example2.Run()
+    End Sub
+End Class
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/Project.vbproj b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/Project.vbproj
@@ -1,8 +1,8 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <OutputType>Library</OutputType>
-    <TargetFrameworks>net8</TargetFrameworks>
+    <OutputType>Exe</OutputType>
+    <TargetFrameworks>net9</TargetFrameworks>
   </PropertyGroup>
 
  </Project>
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/create1.vb b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/create1.vb
@@ -5,7 +5,7 @@ Option Strict On
 Imports System.Numerics
 
 Module Example
-   Public Sub Main()
+   Public Sub Run()
       ' Create a complex number by calling its class constructor.
       Dim c1 As New Complex(12, 6)
       Console.WriteLine(c1)
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/customfmt1.vb b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/customfmt1.vb
@@ -26,7 +26,7 @@ Public Class ComplexFormatter
             Dim fmtString As String = String.Empty
             If fmt.Length > 1 Then
                 Try
-                    precision = Int32.Parse(fmt.Substring(1))
+                    precision = Integer.Parse(fmt.Substring(1))
                 Catch e As FormatException
                     precision = 0
                 End Try
@@ -54,21 +54,20 @@ End Class
 
 ' <Snippet4>
 Module Example2
-    Public Sub Main()
-        Dim c1 As Complex = New Complex(12.1, 15.4)
-        Console.WriteLine("Formatting with ToString():       " +
-                          c1.ToString())
-        Console.WriteLine("Formatting with ToString(format): " +
-                          c1.ToString("N2"))
-        Console.WriteLine("Custom formatting with I0:        " +
-                          String.Format(New ComplexFormatter(), "{0:I0}", c1))
-        Console.WriteLine("Custom formatting with J3:        " +
-                          String.Format(New ComplexFormatter(), "{0:J3}", c1))
+    Public Sub Run()
+        Dim c1 As New Complex(12.1, 15.4)
+        Console.WriteLine($"Formatting with ToString():       {c1}")
+        Console.WriteLine($"Formatting with ToString(format): {c1:N2}")
+        Console.WriteLine($"Custom formatting with I0:        " +
+                          $"{String.Format(New ComplexFormatter(), "{0:I0}", c1)}")
+        Console.WriteLine($"Custom formatting with J3:        " +
+                          $"{String.Format(New ComplexFormatter(), "{0:J3}", c1)}")
     End Sub
 End Module
+
 ' The example displays the following output:
-'    Formatting with ToString():       (12.1, 15.4)
-'    Formatting with ToString(format): (12.10, 15.40)
+'    Formatting with ToString():       <12.1; 15.4>
+'    Formatting with ToString(format): <12.10; 15.40>
 '    Custom formatting with I0:        12 + 15i
 '    Custom formatting with J3:        12.100 + 15.400j
 ' </Snippet4>
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/nan1.vb b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/nan1.vb
@@ -5,7 +5,7 @@ Option Strict On
 Imports System.Numerics
 
 Module Example4
-    Public Sub Main()
+    Public Sub Run()
         Dim c1 As Complex = New Complex(Double.MaxValue / 2, Double.MaxValue / 2)
 
         Dim c2 As Complex = c1 / Complex.Zero
diff --git a/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/precision1.vb b/docs/fundamentals/runtime-libraries/snippets/System.Numerics/Complex/Overview/vb/precision1.vb
@@ -4,7 +4,7 @@ Option Strict On
 Imports System.Numerics
 
 Module Example3
-    Public Sub Main()
+    Public Sub Run()
         ' <Snippet5>
         Dim value As New Complex(Double.MinValue / 2, Double.MinValue / 2)
         Dim value2 As Complex = Complex.Exp(Complex.Log(value))
diff --git a/docs/fundamentals/runtime-libraries/system-numerics-complex.md b/docs/fundamentals/runtime-libraries/system-numerics-complex.md
@@ -1,7 +1,7 @@
 ---
 title: System.Numerics.Complex struct
 description: Learn about the System.Numerics.Complex struct.
-ms.date: 12/31/2023
+ms.date: 05/15/2025
 dev_langs:
   - CSharp
   - VB
@@ -85,11 +85,11 @@ Note that this applies to any intermediate calculations performed by a method. F
 
 ## Format a complex number
 
-By default, the string representation of a complex number takes the form `(`*real*`,` *imaginary*`)`, where *real* and *imaginary* are the string representations of the <xref:System.Double> values that form the complex number's real and imaginary components. Some overloads of the <xref:System.Numerics.Complex.ToString%2A> method allow customization of the string representations of these <xref:System.Double> values to reflect the formatting conventions of a particular culture or to appear in a particular format defined by a standard or custom numeric format string. (For more information, see [Standard Numeric Format Strings](../../standard/base-types/standard-numeric-format-strings.md) and [Custom Numeric Format Strings](../../standard/base-types/custom-numeric-format-strings.md).)
+By default, the string representation of a complex number takes the form `<`*real*`;` *imaginary*`>`, where *real* and *imaginary* are the string representations of the <xref:System.Double> values that form the complex number's real and imaginary components. Some overloads of the <xref:System.Numerics.Complex.ToString%2A> method allow customization of the string representations of these <xref:System.Double> values to reflect the formatting conventions of a particular culture or to appear in a particular format defined by a standard or custom numeric format string. (For more information, see [Standard Numeric Format Strings](../../standard/base-types/standard-numeric-format-strings.md) and [Custom Numeric Format Strings](../../standard/base-types/custom-numeric-format-strings.md).)
 
-One of the more common ways of expressing the string representation of a complex number takes the form a + bi, where a is the complex number's real component, and b is the complex number's imaginary component. In electrical engineering, a complex number is most commonly expressed as a + bj. You can return the string representation of a complex number in either of these two forms. To do this, define a custom format provider by implementing the <xref:System.ICustomFormatter> and <xref:System.IFormatProvider> interfaces, and then call the <xref:System.String.Format%28System.IFormatProvider%2CSystem.String%2CSystem.Object%5B%5D%29?displayProperty=nameWithType> method.
+One of the more common ways of expressing the string representation of a complex number takes the form `a + bi`, where `a` is the complex number's real component, and `b` is the complex number's imaginary component. In electrical engineering, a complex number is most commonly expressed as `a + bj`. You can return the string representation of a complex number in either of these two forms. To do this, define a custom format provider by implementing the <xref:System.ICustomFormatter> and <xref:System.IFormatProvider> interfaces, and then call the <xref:System.String.Format%28System.IFormatProvider%2CSystem.String%2CSystem.Object%5B%5D%29?displayProperty=nameWithType> method.
 
-The following example defines a `ComplexFormatter` class that represents a complex number as a string in the form of either a + bi or a + bj.
+The following example defines a `ComplexFormatter` class that represents a complex number as a string in the form of either `a + bi` or `a + bj`.
 
 :::code language="csharp" source="./snippets/System.Numerics/Complex/Overview/csharp/customfmt1.cs" id="Snippet1":::
 :::code language="vb" source="./snippets/System.Numerics/Complex/Overview/vb/customfmt1.vb" id="Snippet1":::

Original file line number	Diff line number	Diff line change
`@@ -4,7 +4,7 @@`
`4`	`4`
`5`	`5`	`public class CreateEx`
`6`	`6`	`{`
`7`		`- public static void Main()`
	`7`	`+ public static void Run()`
`8`	`8`	`{`
`9`	`9`	`// Create a complex number by calling its class constructor.`
`10`	`10`	`Complex c1 = new Complex(12, 6);`
Original file line number	Diff line number	Diff line change
`@@ -15,17 +15,16 @@ public object GetFormat(Type formatType)`
`15`	`15`	`public string Format(string format, object arg,`
`16`	`16`	`IFormatProvider provider)`
`17`	`17`	`{`
`18`		`- if (arg is Complex)`
	`18`	`+ if (arg is Complex c1)`
`19`	`19`	`{`
`20`		`- Complex c1 = (Complex)arg;`
`21`	`20`	`// Check if the format string has a precision specifier.`
`22`	`21`	`int precision;`
`23`		`- string fmtString = String.Empty;`
	`22`	`+ string fmtString = string.Empty;`
`24`	`23`	`if (format.Length > 1)`
`25`	`24`	`{`
`26`	`25`	`try`
`27`	`26`	`{`
`28`		`- precision = Int32.Parse(format.Substring(1));`
	`27`	`+ precision = int.Parse(format.Substring(1));`
`29`	`28`	`}`
`30`	`29`	`catch (FormatException)`
`31`	`30`	`{`
`@@ -42,12 +41,12 @@ public string Format(string format, object arg,`
`42`	`41`	`}`
`43`	`42`	`else`
`44`	`43`	`{`
`45`		`- if (arg is IFormattable)`
`46`		`- return ((IFormattable)arg).ToString(format, provider);`
	`44`	`+ if (arg is IFormattable formattable)`
	`45`	`+ return formattable.ToString(format, provider);`
`47`	`46`	`else if (arg != null)`
`48`	`47`	`return arg.ToString();`
`49`	`48`	`else`
`50`		`- return String.Empty;`
	`49`	`+ return string.Empty;`
`51`	`50`	`}`
`52`	`51`	`}`
`53`	`52`	`}`
`@@ -56,22 +55,21 @@ public string Format(string format, object arg,`
`56`	`55`	`// <Snippet4>`
`57`	`56`	`public class CustomFormatEx`
`58`	`57`	`{`
`59`		`- public static void Main()`
	`58`	`+ public static void Run()`
`60`	`59`	`{`
`61`		`- Complex c1 = new Complex(12.1, 15.4);`
`62`		`- Console.WriteLine("Formatting with ToString(): " +`
`63`		`- c1.ToString());`
`64`		`- Console.WriteLine("Formatting with ToString(format): " +`
`65`		`- c1.ToString("N2"));`
`66`		`- Console.WriteLine("Custom formatting with I0: " +`
`67`		`- String.Format(new ComplexFormatter(), "{0:I0}", c1));`
`68`		`- Console.WriteLine("Custom formatting with J3: " +`
`69`		`- String.Format(new ComplexFormatter(), "{0:J3}", c1));`
	`60`	`+ Complex c1 = new(12.1, 15.4);`
	`61`	`+ Console.WriteLine($"Formatting with ToString: {c1}");`
	`62`	`+ Console.WriteLine($"Formatting with ToString(format): {c1:N2}");`
	`63`	`+ Console.WriteLine($"Custom formatting with I0:\t" +`
	`64`	`+ $" {string.Format(new ComplexFormatter(), "{0:I0}", c1)}");`
	`65`	`+ Console.WriteLine($"Custom formatting with J3:\t" +`
	`66`	`+ $" {string.Format(new ComplexFormatter(), "{0:J3}", c1)}");`
`70`	`67`	`}`
`71`	`68`	`}`
	`69`	`+`
`72`	`70`	`// The example displays the following output:`
`73`		`-// Formatting with ToString(): (12.1, 15.4)`
`74`		`-// Formatting with ToString(format): (12.10, 15.40)`
	`71`	`+// Formatting with ToString(): <12.1; 15.4>`
	`72`	`+// Formatting with ToString(format): <12.10; 15.40>`
`75`	`73`	`// Custom formatting with I0: 12 + 15i`
`76`	`74`	`// Custom formatting with J3: 12.100 + 15.400j`
`77`	`75`	`// </Snippet4>`
Original file line number	Diff line number	Diff line change
`@@ -4,7 +4,7 @@`
`4`	`4`
`5`	`5`	`public class NaNEx`
`6`	`6`	`{`
`7`		`- public static void Main()`
	`7`	`+ public static void Run()`
`8`	`8`	`{`
`9`	`9`	`Complex c1 = new Complex(Double.MaxValue / 2, Double.MaxValue / 2);`
`10`	`10`
Original file line number	Diff line number	Diff line change
`@@ -1,9 +1,9 @@`
`1`		`-using System;`
	`1`	`+using System;`
`2`	`2`	`using System.Numerics;`
`3`	`3`
`4`	`4`	`public class PrecisionEx`
`5`	`5`	`{`
`6`		`- public static void Main()`
	`6`	`+ public static void Run()`
`7`	`7`	`{`
`8`	`8`	`// <Snippet5>`
`9`	`9`	`Complex value = new Complex(Double.MinValue / 2, Double.MinValue / 2);`