字符串截取

Question

比如 string str="s2g3h4i5dd";
把字符串的偶数位并且是数字的数出来？求解，急！非常感谢了

Answer 1

遍历char[],对偶数位得出char对应数进行比较,是否在48,57之间即可.

Answer 2

string str="s2g3h4i5dd";
char[] c = str.ToCharArray();
string r_str="";
for (int i = 0; i < c.Length; i++)
            {
                if (i%2==1)
                {
                    try{
                        r_str+=Convert.ToString(Convert.ToInt16(c[i]));
                      }
                     catch()
                     {}
                }
            }没测试，思路是这个思路，自己调一下吧

Answer 3

void Main()
{
 string str="s2g3h4i5dd";
 
 var query=str.ToCharArray().Where((s,index)=>index%2>0 &&Regex.IsMatch(s.ToString(),"\\d"));
 Console.WriteLine(new string(query.ToArray()));//2345}

Answer 4

支持这个,然后有一个IsDigit可以判断是否为数字

Answer 5

List<string> list = new List<string>();
            string str = "s2g3h4i5dd";
            char[] chars = str.ToCharArray();
            for (int i = 0; i < chars.Length; i++)
            {
                if (i % 2 != 0)
                {
                    char c=chars[i];
                    if (c >= 48 && c <= 57)
                    {
                        list.Add(c.ToString());
                    }
                }
            }

Answer 6

这样好点
List<string> list = new List<string>();
            string str = "s2g3h4i5dd";
            char[] chars = str.ToCharArray();
            for (int i = 1; i < chars.Length; i += 2)
            {
                char c = chars[i];
                if (c >= 48 && c <= 57)
                {
                    list.Add(c.ToString());
                }
            }

Answer 7

 string str = "s2g3h4i5dd";
            var res =new string(str.Where((c, i) =>
            {
              
                return i % 2> 0 && c >= 48 && c <= 57;
            }).ToArray()) ;

Answer 8

void Main()
{
     string str="s2g3h4i5dd";
     
     var query=str.ToCharArray().Where((s,index)=>index%2>0 &&Regex.IsMatch(s.ToString(),"\\d"));
     Console.WriteLine(new string(query.ToArray()));//2345}
这个好