c - 从 getchar 切换到 fgets

Question

我正在尝试将 getchar 的使用切换为 fgets，但是在使用 getchar 时，整个代码无法正常工作。

//fgets(line, sizeof(line), stdin);

  while(fgets(line, sizeof(line), stdin))
  {
   portNum[sizeof(line)] = (char)line;
  }

while((c = getchar()) != '\n')
{
    portNum[num++] = c;
}
portNum[num] = '\0';

我怎样才能使这两个功能相等才能正常工作？

Answer 1

您对 fgets 的使用是错误的。

fgets Reads characters from stream and stores them as a C string into str until (num-1) characters have been read or either a newline or the end-of-file is reached, whichever happens first.

在您的情况下，fgets 将读取所有字符，直到遇到换行符。

此外，参数使用错误。

char * fgets ( char * str, int num, FILE * stream );

str => Pointer to an array of chars where the string read is copied.

num => Maximum number of characters to be copied into str (including the terminating null-character).

stream => Pointer to a FILE object that identifies an input stream. stdin can be used as argument to read from the standard input.

有关详细信息，请参阅 fgets 文档。

fgets man page