用c语言编写商店销售管理系统

商店销售管理系统的开发需要使用C语言的基本语法、数据结构和文件操作等知识。以下是一个简单的商店销售管理系统的C语言代码示例：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX_ITEMS 100

struct item {
    char name[50];
    int quantity;
    float price;
};

struct item inventory[MAX_ITEMS];
int num_items = 0;

void add_item() {
    struct item new_item;
    printf("Enter name of item: ");
    scanf("%s", new_item.name);
    printf("Enter quantity: ");
    scanf("%d", &new_item.quantity);
    printf("Enter price: ");
    scanf("%f", &new_item.price);
    inventory[num_items] = new_item;
    num_items++;
}

void delete_item() {
    char name[50];
    printf("Enter name of item to delete: ");
    scanf("%s", name);
    int index = -1;
    for (int i = 0; i < num_items; i++) {
        if (strcmp(inventory[i].name, name) == 0) {
            index = i;
            break;
        }
    }
    if (index == -1) {
        printf("Item not found.\n");
    } else {
        for (int i = index; i < num_items - 1; i++) {
            inventory[i] = inventory[i + 1];
        }
        num_items--;
        printf("Item deleted.\n");
    }
}

void display_inventory() {
    printf("Name\tQuantity\tPrice\n");
    for (int i = 0; i < num_items; i++) {
        printf("%s\t%d\t\t%.2f\n", inventory[i].name, inventory[i].quantity, inventory[i].price);
    }
}

void save_inventory() {
    FILE *f = fopen("inventory.txt", "w");
    if (f == NULL) {
        printf("Error opening file.\n");
        return;
    }
    for (int i = 0; i < num_items; i++) {
        fprintf(f, "%s,%d,%.2f\n", inventory[i].name, inventory[i].quantity, inventory[i].price);
    }
    fclose(f);
    printf("Inventory saved.\n");
}

void load_inventory() {
    FILE *f = fopen("inventory.txt", "r");
    if (f == NULL) {
        printf("Error opening file.\n");
        return;
    }
    char line[100];
    while (fgets(line, 100, f) != NULL) {
        char *token = strtok(line, ",");
        strcpy(inventory[num_items].name, token);
        token = strtok(NULL, ",");
        inventory[num_items].quantity = atoi(token);
        token = strtok(NULL, ",");
        inventory[num_items].price = atof(token);
        num_items++;
    }
    fclose(f);
    printf("Inventory loaded.\n");
}

int main() {
    int choice = 0;
    while (choice != 6) {
        printf("\n1. Add item\n");
        printf("2. Delete item\n");
        printf("3. Display inventory\n");
        printf("4. Save inventory\n");
        printf("5. Load inventory\n");
        printf("6. Exit\n");
        printf("Enter choice: ");
        scanf("%d", &choice);
        switch (choice) {
            case 1:
                add_item();
                break;
            case 2:
                delete_item();
                break;
            case 3:
                display_inventory();
                break;
            case 4:
                save_inventory();
                break;
            case 5:
                load_inventory();
                break;
            case 6:
                printf("Goodbye!\n");
                break;
            default:
                printf("Invalid choice.\n");
                break;
        }
    }
    return 0;
}

该程序通过结构体数组存储库存信息，可以添加、删除、显示、保存和加载库存数据。在程序中，库存数据被保存在名为“inventory.txt”的文本文件中。