使用结构和函数时在 C 中初始化字符数组

Question

我编写了一个程序来理解结构和从函数返回结构的概念

struct student
{
    char name[20];
    int age;
    char subject[20];
    int marks;
    int rollno;
}sheet;
struct student display()
{

    sheet.name[20]="Swathi";
    sheet.age=21;
    sheet.subject[20]="Mathematics";
    sheet.marks=85;
    printf("Enter roll no.:");
    scanf("%d",&sheet.rollno);

}
int main()
{   
    struct student sheet1;
    sheet1=display();
    printf("Name:%s",sheet.name);
    printf("Age:%d",sheet.age);

}

我收到 2 条警告消息

warning: assignment makes integer from pointer without a cast [-Wint-conversion]
  sheet.name[20]="Swathi";
warning: assignment makes integer from pointer without a cast [-Wint-conversion]
  sheet.subject[20]="Mathematics";

为什么会这样？我应该如何改变这个？

Answer 1

这里是：

sheet.name[20]="Swathi";

只是获取 "Swathi" 的地址（只读），隐式将该地址转换为 char（使其无用），然后将其分配给 sheet.name[20]（这是越界的，所以是未定义的行为）。相反，试试这个：

strcpy(sheet.name, "Swathi");

与 sheet.subject[20]="Mathematics"; 相同。另请注意，您的 struct student display() 没有返回任何内容，它应该是 void display() 并且不需要 struct student sheet1;。

Answer 2

有效

struct student
{
    char name[20];
    int age;
    char subject[20];
    int marks;
    int rollno;
}sheet;
struct student display()
{

    strcpy(sheet.name, "Swathi");
    sheet.age=21;
    strcpy(sheet.subject,"Mathematics");
    sheet.marks=85;
    printf("Enter roll no.:");
    scanf("%d",&sheet.rollno);

}
int main()
{   
    display();
    printf("Name:%s",sheet.name);
    printf("Age:%d",sheet.age);

}

使用结构和函数时在 C 中初始化字符数组

Initiliasing a character array in C when using structures and functions

c

struct

structure

function