Question

我必须创建一个循环，要求用户从上至下输入第一个数字，如果不满足要求，则用户必须再次输入，直到第一个字母在上而其他字母在下

var novaDrzava = new Država();
Console.Write("Vnesite ime (prva začetnica naj bo velika, ostale male): ");

novaDrzava.Ime = Console.ReadLine();

var drzava = novaDrzava.Ime;
var inicialka = drzava.Substring(0);
var ostale = drzava.Substring(1, drzava.Length - 1);

for (int i = 0; i <= malecrke.Length; i++) {
    if (inicialka.Contains(velikecrke[i])) {
        if (ostale.Contains(malecrke[i])) {
            break;
        } else {
            Console.WriteLine("Ponovno vnesite ime");
            novaDrzava.Ime = Console.ReadLine();
        }
    }
}

Answer 1

保持循环，直到novaDrzava.Ime有效：

  using System.Text.RegularExpressions;

  ...

  Console.Write("Vnesite ime (prva začetnica naj bo velika, ostale male): ");

  // Keep looping
  while (true) {
    // Get a new user input
    //   .Normalize() - let diacritics be represent in a standard way
    //   .Trim()      - let be nice and remove leading/trailinf white spaces 
    novaDrzava.Ime = Console.ReadLine().Normalize().Trim();

    // If input is valid one (uppercase followed zero or more lowercase) 
    // we can stop looping 
    if (Regex.IsMatch(novaDrzava.Ime, @"^\p{Lu}\p{Ll}*$")
      break;

    // input is not valid: let user know it and keep asking
    Console.WriteLine("Ponovno vnesite ime");
  }

  // From now on novaDrzava.Ime contains a valid name

Answer 2

为什么不接受他们的输入并按照您需要的方式对其进行格式化？这将消除对循环的需要。像这样：

OnKeyDown

Answer 3

一个简单的getline就足够了，例如C＆C ++ 只是在内部使用ifs来检查他已经放入的数据，如果满足要求就去检查新数据。

否则，如果他在关键时刻输入了错误的数据，请再次询问他并重置他已经输入的数据。

这是在C中工作的示例，因此您应该能够在C＃中复制它稍作修改，一次输入一个字符。

#include <stdio.h>
#include <stdlib.h>

int is_upper(char *str)
{
    int idx = 0;

  if (str[idx] >= 'a' && str[idx] <= 'z') {
    return (0);
  }
  if (str[idx] >= 'A' && str[idx] <= 'Z') {
    return (1);
  }
  return (2);
}

int main(void)
{
  FILE *fp;
  char *line = NULL;
  size_t len = 0;
  ssize_t read;

  int mystrlen = 0;
  char finalstring[2048]; //to ease the algorithm so there is no need to do a dynamic allocation due to C behavior

  while ((read = getline(&line, &len, stdin)) != -1) {
    if (strlen(line) == 2) { // because \n == 1 char
        if (mystrlen == 0 && line[0] >= 'A' && line[0] <= 'Z') {
            strcat(finalstring, line);
            mystrlen++; //first letter = UPPER CASE
        }
        else if (is_upper(line) == 2 || is_upper(line) == 1 || mystrlen == 0) { //if first letter is good & we aren't at first letter, or simply bad char input
            mystrlen = 0;
            finalstring[0] = '\0';
            printf("reset\n");
        }
        else if (is_upper(line) == 0) { //when all is good
            strcat(finalstring, line);
            printf("\n%s\n", finalstring);
        }
    }
    else {
        mystrlen = 0;
        finalstring[0] = '\0';
        printf("reset\n");
        }
    }
}

创建一个循环，要求输入的第一个字母为大写，而其他字母为小写

3 个答案: