Question

<input type="checkbox" id="activation" name="check" disabled/>

由于字符与空格分隔，因此strlen将其余部分标记为

    垃圾。所以答案总是2.任何想法如何解决？长度是     永远2。         也许它假设空格意味着字符串结尾？         不知道如何修复

Answer 1

除非您另有说明，否则rand()功能会自动播种，值为1.这就是您每次都得到相同答案的原因。

通过对srand的适当调用进行修复，可能取决于您的系统时钟时间。

strlen不会丢弃空格，但会在达到第一个\0时返回。

Answer 2

问题在于：

{
"version": "0.2.0",
"configurations": [
    {
        "name": "Launch",
        "type": "chrome",
        "request": "launch",
        "url": "http://localhost:9000/",//Change to whatever you homepage is
        "runtimeArgs": [
            "--new-window", //Open in new window
            "--user-data-dir=C:/dev/", //Can be any directory. Makes chrome load in a different directory so that it opens in a new instance.
            "--remote-debugging-port=9222" //Open in port 9222 (standard chrome debug port)
        ],
        "webRoot": "src/app/", //The directory that contains js, ts and map files
        "sourceMaps": true
    }
  ]
}

token = strtok((words[random]),search);通过用0终止符替换分隔符来修改其参数;在第一次调用strtok后，strtok变为" c a t "，其长度为2.

您需要在" c"的副本上执行strtok调用，如下所示：

words[random]

修改

不要过于苛刻，但......你的代码是一团糟。我不确定你要完成什么，但你有大量未使用的变量，几种类型不匹配，你的输出令人困惑和不可读等等。糟糕的格式化使代码难以理解和遵循;只是使缩进一致暴露了几个问题（例如冗余的char temp[20]; strcpy( temp, words[random] ); ... token = strtok( temp, search );调用）。 gcc抛出了一堆关于未使用变量的警告，以及srand和srand的缺失声明。

我已经采用了您的代码，并将其重点放在了rand和strtok问题上，并重新格式化了代码和输出，使其具有一定的可读性。结果如下：

strlen

这是输出：

#include <stdio.h> #include <time.h> #include <string.h> #include <stdlib.h> int main(void) { int i; char words[20][20]={" c a t ", " c a r ", " b e a r ", " s h i p ", " m o u s e ", " b e a t l e ", " c o a t ", " n e s t ", " i c e ", " s u g a r ", " b a c o n ", " f r o w n ", " s m i l e ", " d e a d ", " f e a t h e r ", " g o a t ", " h e n ", " j e l l y ", " k o a l a ", " l i p s "}; char* token; const char *search = " "; int random; srand(time(NULL)); for( i=0;i<4;i++) { printf( "%d: ",i ); random = rand() % 20; const char *blanks=" "; printf("%.*s\"%s\", len is %2zu: token list: ",(int) (strlen( blanks ) - (strlen(words[random]))), blanks, words[random], strlen( words[random] )); char *sep = ""; /** * strtok modifies the input string by overwriting the delimiter with * the 0 string terminator; to preserve the contents of words[random], * we need to copy it to a temporary string, and call strtok on that * copy. */ char temp[20]; strcpy( temp, words[random] ); token = strtok( temp, search ); while(token!=NULL) { printf("%s\"%s\"",sep, token); sep = ", "; token = strtok(NULL, search); } putchar( '\n' ); } return 0; }

我不知道您要使用0: " c a r ", len is 7: token list: "c", "a", "r" 1: " b e a t l e ", len is 13: token list: "b", "e", "a", "t", "l", "e" 2: " b e a r ", len is 9: token list: "b", "e", "a", "r" 3: " c a t ", len is 7: token list: "c", "a", "t"和list完成什么，但这至少应该有助于解决您在对字符串进行标记时遇到的任何问题。

c中的strlen错误

2 个答案: