您可以尝试为此问题编写自己的功能。
/**
* Returns a sting "str" centered in string of a length width "new_length".
* Padding is done using the specified fill character "placeholder".
*/
char *
str_center(char str[], unsigned int new_length, char placeholder)
{
size_t str_length = strlen(str);
// if a new length is less or equal length of the original string, returns the original string
if (new_length <= str_length)
return str;
char *buffer;
unsigned int i, total_rest_length;
buffer = malloc(sizeof(char) * new_length);
// length of a wrapper of the original string
total_rest_length = new_length - str_length;
// write a prefix to buffer
i = 0;
while (i < (total_rest_length/2)) {
buffer[i] = placeholder;
++i;
}
buffer[i + 1] = '\0';
// write the original string
strcat(buffer, str);
// write a postfix to the buffer
i += str_length;
while (i < new_length) {
buffer[i] = placeholder;
++i;
}
buffer[i + 1] = '\0';
return buffer;
}
结果:
puts(str_center("A", 0, '-')); // A
puts(str_center("A", 1, '-')); // A
puts(str_center("A", 10, '-')); // ----A-----
puts(str_center("text", 10, '*')); // ***text***
puts(str_center("The C programming language", 26, '!')); // The C programming language
puts(str_center("The C programming language", 27, '!')); // The C programming language!
puts(str_center("The C programming language", 28, '!')); // !The C programming language!
puts(str_center("The C programming language", 29, '!')); // !The C programming language!!
puts(str_center("The C programming language", 30, '!')); // !!The C programming language!!
puts(str_center("The C programming language", 31, '!')); // !!The C programming language!!!
第一个建议:这怎么能不泄露内存中impl'd? – kevinarpe 2017-03-31 13:57:05
如果根据一些看起来不合理的标准预先分配一些缓冲区(例如,对于一个printf不会有超过20个参数将居中,并且没有中心结果会超过200个字节),那么可以让中心函数只是在每次调用时旋转缓冲区。 – hlovdal 2017-04-02 15:18:45