C# | Char。IsLowSurrogate(字符串,Int32)方法

原文:https://www . geesforgeks . org/c-sharp-char-islowasuretestring-int 32-method/

此方法用于指示字符串中指定位置的 Char 对象是否为低代理。

语法:

public static bool IsLowSurrogate (string s, int index);

参数:

s :是一根弦。

索引:是 s 中要评价的人物位置。

返回值:如果 s 参数中指定字符的数值在U+DC00U+DFFF之间,则该方法返回,否则返回

异常:

  • 参数空异常:如果 s 为空。
  • argumentout of range exception:如果指数不在之内。

以下程序说明了字符的使用。IsLowSurrogate(字符串,Int32)方法:

例 1:

// C# program to demonstrate
// Char.IsLowSurrogate(String,
// Int32) Method
using System;

class GFG {

    // Main Method
    public static void Main()
    {
        try {

            // calling check() Method
            check("1234", 3);
            check("Tsunami", 3);
            check("psyc0lo", 4);

            // declaring and initializing string s1
            string s1 = new String(new char[] {'a', 
                        '\uD800', '\uDC00', 'z' });
            check(s1, 2);
        }
        catch (ArgumentNullException e) {

            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
        catch (ArgumentOutOfRangeException e) {

            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }

    // Defining check() method
    public static void check(string s, int i)
    {
        // checking condition
        // using IsLowSurrogate() Method
        bool val = Char.IsLowSurrogate(s, i);

        // checking
        if (val)
            Console.WriteLine("String '{0}' contains Low "
                + "Surrogate value at index {1} ",  s, i);

        else
            Console.WriteLine("String '{0}' does't contain any Low"
                           + "Surrogate value at index {1}", s, i);

    }
}

Output:

String '1234' does't contain any LowSurrogate value at index 3
String 'Tsunami' does't contain any LowSurrogate value at index 3
String 'psyc0lo' does't contain any LowSurrogate value at index 4
String 'að??z' contains Low Surrogate value at index 2

示例 2: 适用于参数异常

// C# program to demonstrate
// Char.IsLowSurrogate(String,
// Int32) Method
using System;

class GFG {

    // Main Method
    public static void Main()
    {
        try {

            // calling check() Method
            check("1234", 3);
            check("Tsunami", 3);
            check("psyc0lo", 4);

            // declaring and initializing string s1
            string s1 = new String(new char[] {'a',
                        '\uD800', '\uDC00', 'z' });
            check(s1, 2);

            Console.WriteLine("");
            Console.WriteLine("s is null");
            check(null, 4);
        }
        catch (ArgumentNullException e) {

            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
        catch (ArgumentOutOfRangeException e) {

            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }

    // Defining check() method
    public static void check(string s, int i)
    {
        // checking condition
        // using IsLowSurrogate() Method
        bool val = Char.IsLowSurrogate(s, i);

        // checking
        if (val)
            Console.WriteLine("String '{0}' contains Low "
                  + "Surrogate value at index {1} ",s, i);

        else
            Console.WriteLine("String '{0}' does't contain any Low"
                            + "Surrogate value at index {1}",s, i);

    }
}

Output:

String '1234' does't contain any LowSurrogate value at index 3
String 'Tsunami' does't contain any LowSurrogate value at index 3
String 'psyc0lo' does't contain any LowSurrogate value at index 4
String 'að??z' contains Low Surrogate value at index 2 

s is null
Exception Thrown: System.ArgumentNullException

例 3:argumentout of range exception

// C# program to demonstrate
// Char.IsLowSurrogate(String,
// Int32) Method
using System;

class GFG {

    // Main Method
    public static void Main()
    {
        try {

            // calling check() Method
            check("1234", 3);
            check("Tsunami", 3);
            check("psyc0lo", 4);

            // declaring and initializing string s1
            string s1 = new String(new char[] {'a',
                        '\uD800', '\uDC00', 'z' });
            check(s1, 2);

            Console.WriteLine("");
            Console.WriteLine("index is less than zero");
            check("null", -4);
        }
        catch (ArgumentNullException e) {

            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
        catch (ArgumentOutOfRangeException e) {

            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }

    // Defining check() method
    public static void check(string s, int i)
    {
        // checking condition
        // using IsLowSurrogate() Method
        bool val = Char.IsLowSurrogate(s, i);

        // checking
        if (val)
            Console.WriteLine("String '{0}' contains Low "
                  + "Surrogate value at index {1} ",s, i);

        else
            Console.WriteLine("String '{0}' does't contain any Low"
                            + "Surrogate value at index {1}",s, i);

    }
}

Output:

String '1234' does't contain any LowSurrogate value at index 3
String 'Tsunami' does't contain any LowSurrogate value at index 3
String 'psyc0lo' does't contain any LowSurrogate value at index 4
String 'að??z' contains Low Surrogate value at index 2 

index is less than zero
Exception Thrown: System.ArgumentOutOfRangeException

参考: