UInt64。用例子解析 C# 中的(字符串)方法

原文:https://www . geesforgeks . org/uint 64-parse string-method-in-c-sharp-with-examples/

UInt64。解析(字符串)方法用于将数字的字符串表示转换为其等效的 64 位无符号整数。

语法:

public static ulong Parse (string str);

这里,字符串是包含要转换的数字的字符串。字符串的格式为【可选空格】【可选符号】数字【可选空格】。这个符号可以是正的,也可以是负的。但是负号只能和零一起使用,否则会抛出overowexception

返回值:是一个 64 位无符号整数,相当于字符串中包含的数字。

异常:

  • 参数空异常:如果字符串为空。
  • 格式异常:如果字符串格式不正确。
  • overoverowexception:如果 str 代表小于T5】MinValueT7】或大于T9】MaxValueT11】的数字。**

以下程序说明了上述方法的使用:

例 1:

// C# program to demonstrate
// UInt64.Parse(String) Method
using System;

class GFG {

    // Main Method
    public static void Main()
    {

        // passing different values
        // to the method to check
        checkParse("18446744073709551615");
        checkParse("454654615,784");
        checkParse("-564564564");
        checkParse(" 119846456456  ");
    }

    // Defining checkParse method
    public static void checkParse(string input)
    {

        try {

            // declaring UInt64 variable
            ulong val;

            // getting parsed value
            val = UInt64.Parse(input);
            Console.WriteLine("'{0}' parsed as {1}", input, val);
        }

        catch (OverflowException) {

            Console.WriteLine("Can't Parsed '{0}'", input);
        }

        catch (FormatException) {

            Console.WriteLine("Can't Parsed '{0}'", input);
        }
    }
}

Output:

'18446744073709551615' parsed as 18446744073709551615
Can't Parsed '454654615,784'
Can't Parsed '-564564564'
' 119846456456  ' parsed as 119846456456

示例 2: 适用于参数异常

// C# program to demonstrate
// UInt64.Parse(String) Method
// for ArgumentNullException
using System;

class GFG {

    // Main Method
    public static void Main()
    {

        try {

            // passing null value as a input
            checkParse(null);
        }

        catch (ArgumentNullException e) {

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

        catch (FormatException e) {

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

    // Defining checkparse method
    public static void checkParse(string input)
    {

        // declaring UInt64 variable
        ulong val;

        // getting parsed value
        val = UInt64.Parse(input);
        Console.WriteLine("'{0}' parsed as {1}", input, val);
    }
}

Output:

Exception Thrown: System.ArgumentNullException

参考: