我想以反向格式打印字符串：
输入： My name is Archit Patel
输出：Patel Archit is name My。
我绑定了以下内容，但它显示为letaP tihcrA si eman ym.
public static string ReverseString(string s)
{
char[] arr = s.ToCharArray();
Array.Reverse(arr);
return new string(arr);
}
您需要将字符串拆分为单词并将其反转而不是反转字符：
text = String.Join(" ", text.Split(' ').Reverse())
在框架 3.5 中：
text = String.Join(" ", text.Split(' ').Reverse().ToArray())
在框架 2.0 中：
string[] words = text.Split(' ');
Array.Reverse(words);
text = String.Join(" ", words);
“请把这个程序的代码发给我。”
好的 ...
using System;
using System.Linq;
class Program
{
static void Main(string[] args)
{
string text = "My name is Archit Patel";
Console.WriteLine(string.Join(" ", text.Split(' ').Reverse()));
}
}
现在：你学到了什么？
此外，正如Guffa 指出的那样，对于 .Net 4.0 以下的版本，您需要添加，因为 string.Join在这些版本.ToArray()中没有正确的重载。
在没有内置函数的情况下试试这个
public string ReverseFullSentence(string inputString)
{
string output = string.Empty;
string[] splitStrings = inputString.Split(' ');
for (int i = splitStrings.Length-1; i > -1 ; i--)
{
output = output + splitStrings[i]+ " ";
}
return output;
}
这应该做你的工作！输出：“Patel Archit 是我的名字”。
static void Main(string[] args)
{
string sentence = "My name is Archit Patel";
StringBuilder sb = new StringBuilder();
string[] split = sentence.Split(' ');
for (int i = split.Length - 1; i > -1; i--)
{
sb.Append(split[i]);
sb.Append(" ");
}
Console.WriteLine(sb);
Console.ReadLine();
}
你可以试试：
string[] words = "My name is Archit Patel".Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
IEnumerable<string> reverseWords = words.Reverse();
string reverseSentence = String.Join(" ", reverseWords);
您可以使用 Stack 来解决此类查询：
String input = "My name is Archit Patel";
Stack<String> st = new Stack<String>();
for(String word : input.split(" "))
st.push(word);
Iterator it = st.iterator();
while(it.hasNext()){
System.out.print(st.pop()+" ");
}
Output String: "Patel Archit is name My"
我很欣赏 Rob Anderson 的回答，但它会反转完整的句子，只需编辑它
string s = "My name is Archit Patel";
string[] words = s.Split(' ');
StringBuilder sb = new StringBuilder();
for (int i = words.Length - 1; i >= 0; i--)
{
sb.Append(words[i]);
sb.Append(" ");
}
Console.WriteLine(sb);
O/P 将是“Patel Archit is name My”
public static string MethodExercise14Logic(string str)
{
string[] sentenceWords = str.Split(' ');
Array.Reverse(sentenceWords);
string newSentence = string.Join(" ", sentenceWords);
return newSentence;
}this.lblStringReverse.Text = 反向（this.txtString.Text）；
private int NoOfWhiteSpaces(string s)
{
char[] sArray = s.ToArray<char>();
int count = 0;
for (int i = 0; i < (sArray.Length - 1); i++)
{
if (sArray[i] == ' ') count++;
}
return count;
}
private string Reverse(string s)
{
char[] sArray = s.ToArray<char>();
int startIndex = 0, lastIndex = 0;
string[] stringArray = new string[NoOfWhiteSpaces(s) + 1];
int stringIndex = 0, whiteSpaceCount = 0;
for (int x = 0; x < sArray.Length; x++)
{
if (sArray[x] == ' ' || whiteSpaceCount == NoOfWhiteSpaces(s))
{
if (whiteSpaceCount == NoOfWhiteSpaces(s))
{
lastIndex = sArray.Length ;
}
else
{
lastIndex = x + 1;
}
whiteSpaceCount++;
char[] sWordArray = new char[lastIndex - startIndex];
int j = 0;
for (int i = startIndex; i < lastIndex; i++)
{
sWordArray[j] = sArray[i];
j++;
}
stringArray[stringIndex] = new string(sWordArray);
stringIndex++;
startIndex = x+1;
}
}
string result = "";
for (int y = stringArray.Length - 1; y > -1; y--)
{
if (result == "")
{
result = stringArray[y];
}
else
{
result = result + ' ' + stringArray[y];
}
}
return result;
}
使用 split 方法将其放入数组中
string[] words = s.Split(' ');
然后用 array.reverse 反转数组
words = Array.Reverse(words);
现在您可以使用 for-each 循环打印它并添加空格
希望这可以帮助
public static string reversewordsInsentence(string sentence)
{
string output = string.Empty;
string word = string.Empty;
foreach(char c in sentence)
{
if (c == ' ')
{
output = word + ' ' + output;
word = string.Empty;
}
else
{
word = word + c;
}
}
output = word + ' ' + output;
return output;
}
如果您想要非 linq 解决方案：
static string ReverseIntact(char[] input)
{
//char[] input = "dog world car life".ToCharArray();
for (int i = 0; i < input.Length / 2; i++)
{//reverse the expression
char tmp = input[i];
input[i] = input[input.Length - i - 1];
input[input.Length - i - 1] = tmp;
}
for (int j = 0, start = 0, end = 0; j <= input.Length; j++)
{
if (j == input.Length || input[j] == ' ')
{
end = j - 1;
for (; start < end; )
{
char tmp = input[start];
input[start] = input[end];
input[end] = tmp;
start++;
end--;
}
start = j + 1;
}
}
return new string(input);
}
public string GetReversedWords(string sentence)
{
try
{
var wordCollection = sentence.Trim().Split(' ');
StringBuilder builder = new StringBuilder();
foreach (var word in wordCollection)
{
var wordAsCharArray = word.ToCharArray();
Array.Reverse(wordAsCharArray);
builder.Append($"{new string(wordAsCharArray)} ");
}
return builder.ToString().Trim();
}
catch(Exception ex)
{
throw new Exception(ex.Message);
}
}
// This Method will reverse word-of-full-sentence without using built-in methods.
public void revSent()
{
string s = "My name is Archit Patel";
List<string> Words = new List<string>(s.Split(' '));
List<string> Rev = new List<string>();
for(int i=Words.Count-1;i>=0;i--)
{
Rev.Add(Words.ElementAt(i));
}
Console.WriteLine(string.Join(" ", Rev));
}
如果您需要就地进行，这是我对面试问题的解决方案。我使用了另外一个字符进行交换。我假设空格仅用作分隔符。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
StringBuilder sb = new StringBuilder("abcd efg hijk");
Reverse(sb, 0 , sb.Length - 1);
Console.WriteLine(sb);
ReverseWords(sb);
Console.WriteLine(sb);
ReverseWordOrder(sb);
Console.WriteLine(sb);
}
static void Reverse(StringBuilder sb, int startIndex, int endIndex)
{
for(int i = startIndex; i <= (endIndex - startIndex) / 2 + startIndex; i++)
{
Swap(sb,i, endIndex + startIndex - i);
}
}
private static void Swap(StringBuilder sb, int index1, int index2)
{
char temp = sb[index1];
sb[index1] = sb[index2];
sb[index2] = temp;
}
static void ReverseWords(StringBuilder sb)
{
int startIndex = 0;
for (int i = 0; i <= sb.Length; i++)
{
if (i == sb.Length || sb[i] == ' ')
{
Reverse(sb, startIndex, i - 1);
startIndex = i + 1;
}
}
}
static void ReverseWordOrder(StringBuilder sb)
{
Reverse(sb, 0, sb.Length - 1);
ReverseWords(sb);
}
}
}
namespace Reverse_the_string
{
class Program
{
static void Main(string[] args)
{
// string text = "my name is bharath";
string text = Console.ReadLine();
string[] words = text.Split(' ');
int k = words.Length - 1;
for (int i = k;i >= 0;i--)
{
Console.Write(words[i] + " " );
}
Console.ReadLine();
}
}
}
不使用拆分和循环
public static string ReverseString(string s)
{
string strToReverse = s;
int fi = strToReverse.IndexOf(' ');
int li = strToReverse.LastIndexOf(' ');
string fp = strToReverse.Substring(0, strToReverse.IndexOf(' ')).TrimStart(' '); ;
string mp = strToReverse.Substring(fi, li - fi).Trim(' ');
string ep = strToReverse.Substring(strToReverse.LastIndexOf(' ', strToReverse.Length - 1)).TrimStart(' ');
return ep + " " + mp + " " + fp;
}
static void Main(string[] args)
{
string str = "the quick brown fox";
string[] arr = str.Split(' ');
for (int i = arr.Length - 1; i >= 0; i--)
{
Console.Write(arr[i] + " ");
}
Console.Read();
}
string s = "this is a test";
string[] words = s.Split(' ');
StringBuilder sb = new StringBuilder();
for (int i = words.Length - 1; i >= 0; i--)
{
for (int j = words[i].Length -1; j >= 0;j--)
{
sb.Append(words[i][j]);
}
sb.Append(" ");
}
Console.WriteLine(sb);