在編程時(shí)，一簇連續(xù)的內(nèi)存單元，比如數(shù)組或者malloc的內(nèi)存塊,如下的數(shù)組a 或者指針p.

int a[4];

int *p = malloc(4 * sizeof(int));

我們要想修改上述連續(xù)的內(nèi)存塊，可以寫一個(gè)函數(shù)(一維指針做參數(shù)傳入起始地址即可）來搞定。

If you want to pass a single-dimension array as an argument in a function, you would have to declare a formal parameter in one of following three ways and all three declaration methods produce similar results because each tells the compiler that an integer pointer is going to be received. Similarly, you can pass multi-dimensional arrays as formal parameters.

Way-1

Formal parameters as a pointer ?

void myFunction(int *param) {...
}

Way-2

Formal parameters as a sized array ?

void myFunction(int param[10]) {...
}

Way-3

Formal parameters as an unsized array ?

void myFunction(int param[]) {...
}

1. 一維指針做參數(shù)

#include <stdio.h>
#define ARRAY_SIZE(arr) (sizeof(arr)/sizeof(arr[0]))void arrayDouble(int *p, int size)
{for (int i=0; i<size; i++){*(p+i) = *(p+i) * 2;}
}void arrayDouble1(int p[], int size)
{for (int i=0; i<size; i++){p[i] = p[i] * 2;}
}void arrayDouble2(int p[4], int size)
{for (int i=0; i<size; i++){p[i] = p[i] * 2;}
}int main()
{int arr[] = {1, 2, 3, 4};for (int i=0; i<ARRAY_SIZE(arr); i++){printf("%d ", arr[i]);}printf("\n");arrayDouble(arr, ARRAY_SIZE(arr));for (int i=0; i<ARRAY_SIZE(arr); i++){printf("%d ", arr[i]);}	printf("\n");arrayDouble1(arr, ARRAY_SIZE(arr));for (int i=0; i<ARRAY_SIZE(arr); i++){printf("%d ", arr[i]);}printf("\n");arrayDouble2(arr, ARRAY_SIZE(arr));for (int i=0; i<ARRAY_SIZE(arr); i++){printf("%d ", arr[i]);}printf("\n");return 0;
}

?上述code運(yùn)行結(jié)果：

1 2 3 4?
2 4 6 8?
4 8 12 16?
8 16 24 32?
?

2. 兩維指針做參數(shù)

用兩維數(shù)組做參數(shù)也可以一簇連續(xù)的內(nèi)存單元的值，只是沒有必要，大材小用，炫技而已，或者對(duì)指針操作含糊不清。

#include <stdio.h>
#define ARRAY_SIZE(arr) (sizeof(arr)/sizeof(arr[0]))void arrayDouble(int **pp, int size)
{int *p = *pp;for (int i=0; i<size; i++){*(p+i) = *(p+i) * 2;}	
}/* arrayDouble1 is the same as arrayDouble,just without temp variable */
void arrayDouble1(int **pp, int size)
{for (int i=0; i<size; i++){*(*pp+i) = *(*pp+i) * 2;}	
}int main()
{int arr[] = {1, 2, 3, 4};int *p = &arr[0];for (int i=0; i<ARRAY_SIZE(arr); i++){printf("%d ", arr[i]);}printf("\n");arrayDouble(&p, ARRAY_SIZE(arr));for (int i=0; i<ARRAY_SIZE(arr); i++){printf("%d ", arr[i]);}	printf("\n");arrayDouble1(&p, ARRAY_SIZE(arr));for (int i=0; i<ARRAY_SIZE(arr); i++){printf("%d ", arr[i]);}	printf("\n");return 0;
}

?運(yùn)行結(jié)果：

1 2 3 4?
2 4 6 8?
4 8 12 16?

總結(jié)

以上是生活随笔為你收集整理的连续地址数据(数组或者malloc的内存)作为函数参数的全部?jī)?nèi)容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網(wǎng)站內(nèi)容還不錯(cuò)，歡迎將生活随笔推薦給好友。