C# 数据类型转换

1、int 和 byte[] 互转

// int32 转 byte[]
byte[] bytes = BitConverter.GetBytes(num);

// byte[] 转 int32
int temp = BitConverter.ToInt32(bytes, 0);

2、int 和 string 互转

// int 转string
int a = 15;
string s1 = a.ToString();
string s2 = Convert.ToString(a);

//string 转 int
string s = "18";
int a3 = Convert.ToInt32(s);
int a1 = int.Parse(s);

3、string 和 byte[] 互转

byte[]转string：
string str = System.Text.Encoding.Default.GetString(byteArray);

string转byte[]：
byte[] byteArray = System.Text.Encoding.Default.GetBytes(str);

ASCII byte[]转string：
string str = System.Text.Encoding.ASCII.GetString ( byteArray );

string转ASCII byte[]：
byte[] byteArray = System.Text.Encoding.ASCII.GetBytes ( str );

4、string 和 string[] 互转

// string 转 string[]
string s = "ab cd ef gh";
string[] sArray = s.Split(' ');

// String[] 转 String
string[] sArray = {"ab", "cd", "ef", "gh"};
string s = string.Join(" ", sArray);

5、string[] 和 List < string > 互转

// string[] 转 List<string>
string[] sArray = { "ab", "cd", "ef", "gh" };
List<string> list = new List<string>(sArray);

// List<String> 转 String[]
List<String> list = new List<string>{"ab","cd","ef","gh"};
string[] sArray = list.ToArray();

6、List< int > 和 string 互转

// List< int > 转 string
List<int> list= new List<int>() { 1, 2, 3, 4, 5, 6, 7 };
string depaid = string.Join(",", list);

// string 转 List< int >
string s = "1, 2, 3";
List<string> list = new List<string>(s.Split(','));

7、List< int > 和 List< string > 互转

// List<int> 转 List<string>
List<int> l1 = new List<int>(new int[] { 1,2,3 } );
List<string> l2 = l1.ConvertAll<string>(x => x.ToString());

// List<string> 转 List<int>
var listOfStrings =(new[]{"4","5","6"}).ToList();
var listOfInts = listOfStrings.Select<string,int>(q =>Convert.ToInt32(q));