StringSplitOptions 枚举

定义

指定适用的 Split 方法重载的选项,例如,是省略返回的数组中的空子字符串,还是从子字符串中剪裁空白。Specifies options for applicable Split method overloads, such as whether to omit empty substrings from the returned array or trim whitespace from substrings.

此枚举有一个 FlagsAttribute 属性,允许按位组合成员值。

public enum class StringSplitOptions
public enum StringSplitOptions
[System.Flags]
public enum StringSplitOptions
[System.Flags]
[System.Runtime.InteropServices.ComVisible(false)]
public enum StringSplitOptions
type StringSplitOptions = 
[<System.Flags>]
type StringSplitOptions = 
[<System.Flags>]
[<System.Runtime.InteropServices.ComVisible(false)>]
type StringSplitOptions = 
Public Enum StringSplitOptions
继承
StringSplitOptions
属性

字段

None 0

在拆分字符串时使用默认选项。Use the default options when splitting strings.

RemoveEmptyEntries 1

省略结果中包含空字符串的数组元素。Omit array elements that contain an empty string from the result.

TrimEntries 2

剪裁结果中每个子字符串的空白字符。Trim white-space characters from each substring in the result.

示例

下面的示例演示如何 StringSplitOptions 使用枚举来包括或排除方法生成的子字符串 String.SplitThe following example shows how the StringSplitOptions enumeration is used to include or exclude substrings generated by the String.Split method:

// This example demonstrates the String.Split(Char[], Boolean) and 
//                               String.Split(Char[], Int32, Boolean) methods
using namespace System;
void Show( array<String^>^entries )
{
   Console::WriteLine( "The return value contains these {0} elements:", entries->Length );
   System::Collections::IEnumerator^ myEnum = entries->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      String^ entry = safe_cast<String^>(myEnum->Current);
      Console::Write( "<{0}>", entry );
   }

   Console::Write( "{0}{0}", Environment::NewLine );
}

int main()
{
   String^ s = ",one,,,two,,,,,three,,";
   array<Char>^sep = gcnew array<Char>{
      ','
   };
   array<String^>^result;
   
   //
   Console::WriteLine( "The original string is \"{0}\".", s );
   Console::WriteLine( "The separation character is '{0}'.", sep[ 0 ] );
   Console::WriteLine();
   
   //
   Console::WriteLine( "Split the string and return all elements:" );
   result = s->Split( sep, StringSplitOptions::None );
   Show( result );
   
   //
   Console::WriteLine( "Split the string and return all non-empty elements:" );
   result = s->Split( sep, StringSplitOptions::RemoveEmptyEntries );
   Show( result );
   
   //
   Console::WriteLine( "Split the string and return 2 elements:" );
   result = s->Split( sep, 2, StringSplitOptions::None );
   Show( result );
   
   //
   Console::WriteLine( "Split the string and return 2 non-empty elements:" );
   result = s->Split( sep, 2, StringSplitOptions::RemoveEmptyEntries );
   Show( result );
}

/*
This example produces the following results:

The original string is ",one,,,two,,,,,three,,".
The separation character is ','.

Split the string and return all elements:
The return value contains these 12 elements:
<><one><><><two><><><><><three><><>

Split the string and return all non-empty elements:
The return value contains these 3 elements:
<one><two><three>

Split the string and return 2 elements:
The return value contains these 2 elements:
<><one,,,two,,,,,three,,>

Split the string and return 2 non-empty elements:
The return value contains these 2 elements:
<one><,,two,,,,,three,,>

*/
// This example demonstrates the String.Split() methods that use
// the StringSplitOptions enumeration.
string s1 = ",ONE,,TWO,,,THREE,,";
string s2 = "[stop]" +
            "ONE[stop][stop]" +
            "TWO[stop][stop][stop]" +
            "THREE[stop][stop]";
char[] charSeparators = new char[] { ',' };
string[] stringSeparators = new string[] { "[stop]" };
string[] result;
// ------------------------------------------------------------------------------
// Split a string delimited by characters.
// ------------------------------------------------------------------------------
Console.WriteLine("1) Split a string delimited by characters:\n");

// Display the original string and delimiter characters.
Console.WriteLine($"1a) The original string is \"{s1}\".");
Console.WriteLine($"The delimiter character is '{charSeparators[0]}'.\n");

// Split a string delimited by characters and return all elements.
Console.WriteLine("1b) Split a string delimited by characters and " +
                  "return all elements:");
result = s1.Split(charSeparators, StringSplitOptions.None);
Show(result);

// Split a string delimited by characters and return all non-empty elements.
Console.WriteLine("1c) Split a string delimited by characters and " +
                  "return all non-empty elements:");
result = s1.Split(charSeparators, StringSplitOptions.RemoveEmptyEntries);
Show(result);

// Split the original string into the string and empty string before the
// delimiter and the remainder of the original string after the delimiter.
Console.WriteLine("1d) Split a string delimited by characters and " +
                  "return 2 elements:");
result = s1.Split(charSeparators, 2, StringSplitOptions.None);
Show(result);

// Split the original string into the string after the delimiter and the
// remainder of the original string after the delimiter.
Console.WriteLine("1e) Split a string delimited by characters and " +
                  "return 2 non-empty elements:");
result = s1.Split(charSeparators, 2, StringSplitOptions.RemoveEmptyEntries);
Show(result);

// ------------------------------------------------------------------------------
// Split a string delimited by another string.
// ------------------------------------------------------------------------------
Console.WriteLine("2) Split a string delimited by another string:\n");

// Display the original string and delimiter string.
Console.WriteLine($"2a) The original string is \"{s2}\".");
Console.WriteLine($"The delimiter string is \"{stringSeparators[0]}\".\n");

// Split a string delimited by another string and return all elements.
Console.WriteLine("2b) Split a string delimited by another string and " +
                  "return all elements:");
result = s2.Split(stringSeparators, StringSplitOptions.None);
Show(result);

// Split the original string at the delimiter and return all non-empty elements.
Console.WriteLine("2c) Split a string delimited by another string and " +
                  "return all non-empty elements:");
result = s2.Split(stringSeparators, StringSplitOptions.RemoveEmptyEntries);
Show(result);

// Split the original string into the empty string before the
// delimiter and the remainder of the original string after the delimiter.
Console.WriteLine("2d) Split a string delimited by another string and " +
                  "return 2 elements:");
result = s2.Split(stringSeparators, 2, StringSplitOptions.None);
Show(result);

// Split the original string into the string after the delimiter and the
// remainder of the original string after the delimiter.
Console.WriteLine("2e) Split a string delimited by another string and " +
                  "return 2 non-empty elements:");
result = s2.Split(stringSeparators, 2, StringSplitOptions.RemoveEmptyEntries);
Show(result);

// Display the array of separated strings using a local function
void Show(string[] entries)
{
    Console.WriteLine($"The return value contains these {entries.Length} elements:");
    foreach (string entry in entries)
    {
        Console.Write($"<{entry}>");
    }
    Console.Write("\n\n");
}

/*
This example produces the following results:

1) Split a string delimited by characters:

1a) The original string is ",ONE,,TWO,,,THREE,,".
The delimiter character is ','.

1b) Split a string delimited by characters and return all elements:
The return value contains these 9 elements:
<><ONE><><TWO><><><THREE><><>

1c) Split a string delimited by characters and return all non-empty elements:
The return value contains these 3 elements:
<ONE><TWO><THREE>

1d) Split a string delimited by characters and return 2 elements:
The return value contains these 2 elements:
<><ONE,,TWO,,,THREE,,>

1e) Split a string delimited by characters and return 2 non-empty elements:
The return value contains these 2 elements:
<ONE><TWO,,,THREE,,>

2) Split a string delimited by another string:

2a) The original string is "[stop]ONE[stop][stop]TWO[stop][stop][stop]THREE[stop][stop]".
The delimiter string is "[stop]".

2b) Split a string delimited by another string and return all elements:
The return value contains these 9 elements:
<><ONE><><TWO><><><THREE><><>

2c) Split a string delimited by another string and return all non-empty elements:
The return value contains these 3 elements:
<ONE><TWO><THREE>

2d) Split a string delimited by another string and return 2 elements:
The return value contains these 2 elements:
<><ONE[stop][stop]TWO[stop][stop][stop]THREE[stop][stop]>

2e) Split a string delimited by another string and return 2 non-empty elements:
The return value contains these 2 elements:
<ONE><TWO[stop][stop][stop]THREE[stop][stop]>

*/
    Dim s1 As String = ",ONE,,TWO,,,THREE,,"
    Dim s2 As String = "[stop]" &
                       "ONE[stop][stop]" &
                       "TWO[stop][stop][stop]" &
                       "THREE[stop][stop]"
    Dim charSeparators() As Char = {","c}
    Dim stringSeparators() As String = {"[stop]"}
    Dim result() As String
    ' ------------------------------------------------------------------------------
    ' Split a string delimited by characters.
    ' ------------------------------------------------------------------------------
    Console.WriteLine("1) Split a string delimited by characters:" & vbCrLf)

    ' Display the original string and delimiter characters.
    Console.WriteLine("1a) The original string is ""{0}"".", s1)
    Console.WriteLine("The delimiter character is '{0}'." & vbCrLf, charSeparators(0))

    ' Split a string delimited by characters and return all elements.
    Console.WriteLine("1b) Split a string delimited by characters and " &
                      "return all elements:")
    result = s1.Split(charSeparators, StringSplitOptions.None)
    Show(result)

    ' Split a string delimited by characters and return all non-empty elements.
    Console.WriteLine("1c) Split a string delimited by characters and " &
                      "return all non-empty elements:")
    result = s1.Split(charSeparators, StringSplitOptions.RemoveEmptyEntries)
    Show(result)

    ' Split the original string into the string and empty string before the 
    ' delimiter and the remainder of the original string after the delimiter.
    Console.WriteLine("1d) Split a string delimited by characters and " &
                      "return 2 elements:")
    result = s1.Split(charSeparators, 2, StringSplitOptions.None)
    Show(result)

    ' Split the original string into the string after the delimiter and the 
    ' remainder of the original string after the delimiter.
    Console.WriteLine("1e) Split a string delimited by characters and " &
                      "return 2 non-empty elements:")
    result = s1.Split(charSeparators, 2, StringSplitOptions.RemoveEmptyEntries)
    Show(result)

    ' ------------------------------------------------------------------------------
    ' Split a string delimited by another string.
    ' ------------------------------------------------------------------------------
    Console.WriteLine("2) Split a string delimited by another string:" & vbCrLf)

    ' Display the original string and delimiter string.
    Console.WriteLine("2a) The original string is ""{0}"".", s2)
    Console.WriteLine("The delimiter string is ""{0}""." & vbCrLf, stringSeparators(0))

    ' Split a string delimited by another string and return all elements.
    Console.WriteLine("2b) Split a string delimited by another string and " &
                      "return all elements:")
    result = s2.Split(stringSeparators, StringSplitOptions.None)
    Show(result)

    ' Split the original string at the delimiter and return all non-empty elements.
    Console.WriteLine("2c) Split a string delimited by another string and " &
                      "return all non-empty elements:")
    result = s2.Split(stringSeparators, StringSplitOptions.RemoveEmptyEntries)
    Show(result)

    ' Split the original string into the empty string before the 
    ' delimiter and the remainder of the original string after the delimiter.
    Console.WriteLine("2d) Split a string delimited by another string and " &
                      "return 2 elements:")
    result = s2.Split(stringSeparators, 2, StringSplitOptions.None)
    Show(result)

    ' Split the original string into the string after the delimiter and the 
    ' remainder of the original string after the delimiter.
    Console.WriteLine("2e) Split a string delimited by another string and " &
                      "return 2 non-empty elements:")
    result = s2.Split(stringSeparators, 2, StringSplitOptions.RemoveEmptyEntries)
    Show(result)

End Sub


' Display the array of separated strings.
Public Shared Sub Show(ByVal entries() As String)
    Console.WriteLine("The return value contains these {0} elements:", entries.Length)
    Dim entry As String
    For Each entry In entries
        Console.Write("<{0}>", entry)
    Next entry
    Console.Write(vbCrLf & vbCrLf)

End Sub

'This example produces the following results:
'
'1) Split a string delimited by characters:
'
'1a) The original string is ",ONE,,TWO,,,THREE,,".
'The delimiter character is ','.
'
'1b) Split a string delimited by characters and return all elements:
'The return value contains these 9 elements:
'<><ONE><><TWO><><><THREE><><>
'
'1c) Split a string delimited by characters and return all non-empty elements:
'The return value contains these 3 elements:
'<ONE><TWO><THREE>
'
'1d) Split a string delimited by characters and return 2 elements:
'The return value contains these 2 elements:
'<><ONE,,TWO,,,THREE,,>
'
'1e) Split a string delimited by characters and return 2 non-empty elements:
'The return value contains these 2 elements:
'<ONE><TWO,,,THREE,,>
'
'2) Split a string delimited by another string:
'
'2a) The original string is "[stop]ONE[stop][stop]TWO[stop][stop][stop]THREE[stop][stop]".
'The delimiter string is "[stop]".
'
'2b) Split a string delimited by another string and return all elements:
'The return value contains these 9 elements:
'<><ONE><><TWO><><><THREE><><>
'
'2c) Split a string delimited by another string and return all non-empty elements:
'The return value contains these 3 elements:
'<ONE><TWO><THREE>
'
'2d) Split a string delimited by another string and return 2 elements:
'The return value contains these 2 elements:
'<><ONE[stop][stop]TWO[stop][stop][stop]THREE[stop][stop]>
'
'2e) Split a string delimited by another string and return 2 non-empty elements:
'The return value contains these 2 elements:
'<ONE><TWO[stop][stop][stop]THREE[stop][stop]>
'

注解

String.Split方法返回给定字符串中由指定字符或字符串分隔的子字符串的数组。The String.Split method returns an array of the substrings in a given string that are delimited by specified characters or strings. 相邻分隔符将生成一个数组元素,该元素包含一个 () 的空字符串 ""Adjacent delimiters yield an array element that contains an empty string (""). 枚举的字段之一 StringSplitOptions 指定包含空字符串的元素是否应包含在返回的数组中。One of the fields of the StringSplitOptions enumeration specifies whether an element that contains an empty string should be included in the returned array.

指定 None 字段以调用方法的默认行为,该 String.Split 方法不会剪裁空白字符并包含空子字符串。Specify the None field to invoke the default behavior of the String.Split method, which is not to trim white-space characters and to include empty substrings.

适用于

另请参阅