C 语言在字符串中替换所有出现的字符

编写一个 C 语言程序，用示例替换字符串中的所有字符。

C 语言程序在字符串中替换所有出现的字符示例

此程序允许用户输入一个字符串（或字符数组）和一个字符值。接下来，它将搜索并替换字符串中出现的所有字符。

#include <stdio.h>
#include <string.h>
 
int main()
{
  	char str[100], ch, Newch;
  	int i;
 
  	printf("\n Please Enter any String :  ");
  	gets(str);
  	
  	printf("\n Please Enter the Character that you want to Search for :  ");
  	scanf("%c", &ch);
  	
  	getchar();
  	
  	printf("\n Please Enter the New Character :  ");
  	scanf("%c", &Newch);
  	
  	for(i = 0; i <= strlen(str); i++)
  	{
  		if(str[i] == ch)  
		{
  			str[i] = Newch;
 		}
	}
	
	printf("\n The Final String after Replacing All Occurrences of '%c' with '%c' = %s ", ch, Newch, str);
	
  	return 0;
}

首先，我们使用 For 循环 遍历字符串中的每个字符。

for(i = 0; i < strlen(str); i++)
{
	if(str[i] == ch)  
	{
		str[i] = Newch;  	
	}
}

str[] = Hello
ch = l
Newch = @

For 循环第一次迭代：for(i = 0; i < strlen(str); i++)

在 C 编程 While 循环中，我们使用 If 语句 来检查 str[0] 是否等于用户指定的字符。

if(str[i] == ch) => if(H == l) – 条件为 False。因此，i 值将被递增。

第二次迭代：for(i = 1; 1 < 5; 1++)

if(str[i] == ch) => if(e == l) – 条件为 False。因此，i 将递增。

第三次迭代：for(i = 2; 2 < 5; 2++)
if(str[i] == ch) => if(l == l) – 条件为 True。
str[i] = Newch
str[2] = @

第四次迭代：for(i = 3; 3 < 5; 3++)
if(str[i] == ch) => if(l == l) – 条件为 True。
str[i] = Newch
str[3] = @

第五次迭代：for(i = 4; 4 < 5; 4++)
if(str[i] == ch) => if(0 == l) – 条件为 False。
str[i] = Newch
str[3] = @
以上条件为 False。

接下来，我们使用 printf 语句打印最终字符串。

printf("\n The Final String after Replacing All Occurrences of '%c' with '%c' = %s ", ch, Newch, str);

C 语言程序在字符串中替换所有出现的字符示例 2

此 程序 用于替换所有字符出现次数，与上面相同。这里，我们只是将 For 循环替换为 While 循环。

#include <stdio.h>
#include <string.h>
 
int main()
{
  	char str[100], ch, Newch;
  	int i = 0;
 
  	printf("\n Please Enter any String :  ");
  	gets(str);
  	
  	printf("\n Please Enter the Character that you want to Search for :  ");
  	scanf("%c", &ch);
  	
  	getchar();
  	
  	printf("\n Please Enter the New Character :  ");
  	scanf("%c", &Newch);
  	
  	while(str[i] != '\0')
  	{
  		if(str[i] == ch)  
		{
  			str[i] = Newch;
 		}
 		i++;
	}
	
	printf("\n The Final String after Replacing All Occurrences of '%c' with '%c' = %s ", ch, Newch, str);
	
  	return 0;
}

 Please Enter any String :  tutorial gateway

 Please Enter the Character that you want to Search for :  t

 Please Enter the New Character :  $

 The Final String after Replacing All Occurrences of 't' with '$' = $u$orial ga$eway

C 语言程序在字符串中替换所有出现的字符示例 3

此 程序 用于替换所有字符出现次数，与第一个示例相同。但是，这次我们使用了 函数 概念来分离逻辑。

#include <stdio.h>
#include <string.h>

void Replace_AllOccurrence(char *str, char ch, char Newch);
 
int main()
{
  	char str[100], ch, Newch;
  	int i = 0;
 
  	printf("\n Please Enter any String :  ");
  	gets(str);
  	
  	printf("\n Please Enter the Character that you want to Replace :  ");
  	scanf("%c", &ch);
  	
  	getchar();
  	
  	printf("\n Please Enter the New Character :  ");
  	scanf("%c", &Newch);
  	
  	Replace_AllOccurrence(str, ch, Newch);
  	
  	printf("\n The Final String after Replacing All Occurrences of '%c' with '%c' = %s ", ch, Newch, str);
	
  	return 0;
}

void Replace_AllOccurrence(char *str, char ch, char Newch)
{
	int i;

	for(i = 0; str[i] != '\0'; i++)
	{
		if(str[i] == ch)
		{
			str[i] = Newch;
		}  
	}
}

 Please Enter any String :  Welcome to c programming examples

 Please Enter the Character that you want to Replace :  m

 Please Enter the New Character :  #

 The Final String after Replacing All Occurrences of 'm' with '#' = Welco#e to c progra##ing exa#ples