如何将整数转换为二进制表示?

我正在使用下面的代码:

String input = "8";
String output = Convert.ToInt32(input, 2).ToString();

但是它抛出了一个异常:

找不到任何可解析的数字


当前回答

我在一个编码挑战中遇到了这个问题,你必须将32位十进制转换为二进制,并找到子字符串的可能组合。

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Numerics;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp2
{
    class Program
    {

        public static void Main()
        {
            int numberofinputs = int.Parse(Console.ReadLine());
            List<BigInteger> inputdecimal = new List<BigInteger>();
            List<string> outputBinary = new List<string>();


            for (int i = 0; i < numberofinputs; i++)
            {
                inputdecimal.Add(BigInteger.Parse(Console.ReadLine(), CultureInfo.InvariantCulture));
            }
            //processing begins 

            foreach (var n in inputdecimal)
            {
                string binary = (binaryconveter(n));
                subString(binary, binary.Length);
            }

            foreach (var item in outputBinary)
            {
                Console.WriteLine(item);
            }

            string binaryconveter(BigInteger n)
            {
                int i;
                StringBuilder output = new StringBuilder();

                for (i = 0; n > 0; i++)
                {
                    output = output.Append(n % 2);
                    n = n / 2;
                }

                return output.ToString();
            }

            void subString(string str, int n)
            {
                int zeroodds = 0;
                int oneodds = 0;

                for (int len = 1; len <= n; len++)
                {

                    for (int i = 0; i <= n - len; i++)
                    {
                        int j = i + len - 1;

                        string substring = "";
                        for (int k = i; k <= j; k++)
                        {
                            substring = String.Concat(substring, str[k]);

                        }
                        var resultofstringanalysis = stringanalysis(substring);
                        if (resultofstringanalysis.Equals("both are odd"))
                        {
                            ++zeroodds;
                            ++oneodds;
                        }
                        else if (resultofstringanalysis.Equals("zeroes are odd"))
                        {
                            ++zeroodds;
                        }
                        else if (resultofstringanalysis.Equals("ones are odd"))
                        {
                            ++oneodds;
                        }

                    }
                }
                string outputtest = String.Concat(zeroodds.ToString(), ' ', oneodds.ToString());
                outputBinary.Add(outputtest);
            }

            string stringanalysis(string str)
            {
                int n = str.Length;

                int nofZeros = 0;
                int nofOnes = 0;

                for (int i = 0; i < n; i++)
                {
                    if (str[i] == '0')
                    {
                        ++nofZeros;
                    }
                    if (str[i] == '1')
                    {
                        ++nofOnes;
                    }

                }
                if ((nofZeros != 0 && nofZeros % 2 != 0) && (nofOnes != 0 && nofOnes % 2 != 0))
                {
                    return "both are odd";
                }
                else if (nofZeros != 0 && nofZeros % 2 != 0)
                {
                    return "zeroes are odd";
                }
                else if (nofOnes != 0 && nofOnes % 2 != 0)
                {
                    return "ones are odd";
                }
                else
                {
                    return "nothing";
                }

            }
            Console.ReadKey();
        }

    }
}

其他回答

using System;

class Program 
{
    static void Main(string[] args) {

        try {

            int i = (int) Convert.ToInt64(args[0]);
            Console.WriteLine("\n{0} converted to Binary is {1}\n", i, ToBinary(i));

        } catch(Exception e) {
            Console.WriteLine("\n{0}\n", e.Message);
        }
    }

    public static string ToBinary(Int64 Decimal) {
        // Declare a few variables we're going to need
        Int64 BinaryHolder;
        char[] BinaryArray;
        string BinaryResult = "";

        while (Decimal > 0) {
            BinaryHolder = Decimal % 2;
            BinaryResult += BinaryHolder;
            Decimal = Decimal / 2;
        }

        BinaryArray = BinaryResult.ToCharArray();
        Array.Reverse(BinaryArray);
        BinaryResult = new string(BinaryArray);

        return BinaryResult;
    }
}

转换。ToInt32(string, base)不会将基数转换为基数。它假设字符串包含一个以指定基数为底的有效数字,并转换为以10为基数。

所以你会得到一个错误,因为“8”不是一个以2为基数的有效数字。

String str = "1111";
String Ans = Convert.ToInt32(str, 2).ToString();

将显示15(1111以2为底= 15以10为底)

String str = "f000";
String Ans = Convert.ToInt32(str, 16).ToString();

将显示61440。

我在一个编码挑战中遇到了这个问题,你必须将32位十进制转换为二进制,并找到子字符串的可能组合。

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Numerics;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp2
{
    class Program
    {

        public static void Main()
        {
            int numberofinputs = int.Parse(Console.ReadLine());
            List<BigInteger> inputdecimal = new List<BigInteger>();
            List<string> outputBinary = new List<string>();


            for (int i = 0; i < numberofinputs; i++)
            {
                inputdecimal.Add(BigInteger.Parse(Console.ReadLine(), CultureInfo.InvariantCulture));
            }
            //processing begins 

            foreach (var n in inputdecimal)
            {
                string binary = (binaryconveter(n));
                subString(binary, binary.Length);
            }

            foreach (var item in outputBinary)
            {
                Console.WriteLine(item);
            }

            string binaryconveter(BigInteger n)
            {
                int i;
                StringBuilder output = new StringBuilder();

                for (i = 0; n > 0; i++)
                {
                    output = output.Append(n % 2);
                    n = n / 2;
                }

                return output.ToString();
            }

            void subString(string str, int n)
            {
                int zeroodds = 0;
                int oneodds = 0;

                for (int len = 1; len <= n; len++)
                {

                    for (int i = 0; i <= n - len; i++)
                    {
                        int j = i + len - 1;

                        string substring = "";
                        for (int k = i; k <= j; k++)
                        {
                            substring = String.Concat(substring, str[k]);

                        }
                        var resultofstringanalysis = stringanalysis(substring);
                        if (resultofstringanalysis.Equals("both are odd"))
                        {
                            ++zeroodds;
                            ++oneodds;
                        }
                        else if (resultofstringanalysis.Equals("zeroes are odd"))
                        {
                            ++zeroodds;
                        }
                        else if (resultofstringanalysis.Equals("ones are odd"))
                        {
                            ++oneodds;
                        }

                    }
                }
                string outputtest = String.Concat(zeroodds.ToString(), ' ', oneodds.ToString());
                outputBinary.Add(outputtest);
            }

            string stringanalysis(string str)
            {
                int n = str.Length;

                int nofZeros = 0;
                int nofOnes = 0;

                for (int i = 0; i < n; i++)
                {
                    if (str[i] == '0')
                    {
                        ++nofZeros;
                    }
                    if (str[i] == '1')
                    {
                        ++nofOnes;
                    }

                }
                if ((nofZeros != 0 && nofZeros % 2 != 0) && (nofOnes != 0 && nofOnes % 2 != 0))
                {
                    return "both are odd";
                }
                else if (nofZeros != 0 && nofZeros % 2 != 0)
                {
                    return "zeroes are odd";
                }
                else if (nofOnes != 0 && nofOnes % 2 != 0)
                {
                    return "ones are odd";
                }
                else
                {
                    return "nothing";
                }

            }
            Console.ReadKey();
        }

    }
}

这是一个有趣的阅读,我正在寻找一个快速复制粘贴。 我知道我很久以前用bitmath做过这件事。

以下是我的看法。

// i had this as a extension method in a static class (this int inValue);

public static string ToBinaryString(int inValue)
{
    string result = "";
    for (int bitIndexToTest = 0; bitIndexToTest < 32; bitIndexToTest++)
        result += ((inValue & (1 << (bitIndexToTest))) > 0) ? '1' : '0';
    return result;
}

你可以在循环中加入一些模数。

        // little bit of spacing
        if (((bitIndexToTest + 1) % spaceEvery) == 0)
            result += ' ';

你可能会使用或传入一个stringbuilder,并直接追加或索引,以避免释放,也可以绕过+=的使用;

    int x=550;
    string s=" ";
    string y=" ";

    while (x>0)
    {

        s += x%2;
        x=x/2;
    }


    Console.WriteLine(Reverse(s));
}

public static string Reverse( string s )
{
    char[] charArray = s.ToCharArray();
    Array.Reverse( charArray );
    return new string( charArray );
}