C 結構與函數 · Programiz 中文系列教程

# C 結構與函數 > 原文： [https://www.programiz.com/c-programming/c-structure-function](https://www.programiz.com/c-programming/c-structure-function) #### 在本教程中，您將學習將結構變量作為參數傳遞給函數。您將學習借助示例從函數返回`struct`的方法。與內置類型的變量類似，您也可以將結構變量傳遞給函數。 * * * ## 將結構傳遞給函數我們建議您在學習如何將結構傳遞給函數之前先學習這些教程。 * [C 結構](/c-programming/c-structures) * [C 函數](/c-programming/c-functions) * [用戶定義的函數](/c-programming/c-user-defined-functions) 這是將結構傳遞給函數的方法 ```c #include <stdio.h> struct student { char name[50]; int age; }; // function prototype void display(struct student s); int main() { struct student s1; printf("Enter name: "); // read string input from the user until \n is entered // \n is discarded scanf("%[^\n]%*c", s1.name); printf("Enter age: "); scanf("%d", &s1.age); display(s1); // passing struct as an argument return 0; } void display(struct student s) { printf("\nDisplaying information\n"); printf("Name: %s", s.name); printf("\nAge: %d", s.age); } ``` **輸出** ```c Enter name: Bond Enter age: 13 Displaying information Name: Bond Age: 13 ``` 在此，創建類型為`struct student`的結構變量`s1`。使用`display(s1);`語句將該變量傳遞到`display()`函數。 * * * ## 從函數返回結構這是從函數返回結構的方法： ```c #include <stdio.h> struct student { char name[50]; int age; }; // function prototype struct student getInformation(); int main() { struct student s; s = getInformation(); printf("\nDisplaying information\n"); printf("Name: %s", s.name); printf("\nRoll: %d", s.age); return 0; } struct student getInformation() { struct student s1; printf("Enter name: "); scanf ("%[^\n]%*c", s1.name); printf("Enter age: "); scanf("%d", &s1.age); return s1; } ``` 在此，使用`s = getInformation();`語句調用`getInformation()`函數。該函數返回`struct student`類型的結構。返回的結構通過`main()`函數顯示。注意，`getInformation()`的返回類型也是`struct student`。 * * * ## 按引用傳遞結構您還可以按引用傳遞結構（就像您按引用傳遞內置類型的變量一樣）。我們建議您在繼續之前閱讀[引用傳遞](/c-programming/c-pointer-functions)的文檔。在按引用傳遞期間，結構變量的內存地址將傳遞給函數。 ```c #include <stdio.h> typedef struct Complex { float real; float imag; } complex; void addNumbers(complex c1, complex c2, complex *result); int main() { complex c1, c2, result; printf("For first number,\n"); printf("Enter real part: "); scanf("%f", &c1.real); printf("Enter imaginary part: "); scanf("%f", &c1.imag); printf("For second number, \n"); printf("Enter real part: "); scanf("%f", &c2.real); printf("Enter imaginary part: "); scanf("%f", &c2.imag); addNumbers(c1, c2, &result); printf("\nresult.real = %.1f\n", result.real); printf("result.imag = %.1f", result.imag); return 0; } void addNumbers(complex c1, complex c2, complex *result) { result->real = c1.real + c2.real; result->imag = c1.imag + c2.imag; } ``` **輸出** ```c For first number, Enter real part: 1.1 Enter imaginary part: -2.4 For second number, Enter real part: 3.4 Enter imaginary part: -3.2 result.real = 4.5 result.imag = -5.6 ``` 在上述程序中，三個結構變量`c1`，`c2`和`result`的地址傳遞給`addNumbers()`函數。此處，`result`通過引用傳遞。當`addNumbers()`內的`result`變量被更改時，`main()`函數內的`result`變量也相應地被更改。