esp32 nvs读写idf完整代码

下面是ESP32 NVS读写的完整代码示例，使用ESP-IDF开发框架：

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_system.h"
#include "nvs_flash.h"
#include "nvs.h"

#define STORAGE_NAMESPACE "storage"

void nvs_write(void)
{
    nvs_handle my_handle;
    esp_err_t err = nvs_open(STORAGE_NAMESPACE, NVS_READWRITE, &my_handle);
    if (err != ESP_OK) {
        printf("Error (%s) opening NVS handle!\n", esp_err_to_name(err));
    } else {
        // Write values including string, binary and integer
        uint8_t buf[] = {0x00, 0x01, 0x02, 0x03};
        err = nvs_set_i32(my_handle, "int_val", 123);
        err = nvs_set_str(my_handle, "string_val", "Hello world");
        err = nvs_set_blob(my_handle, "blob_val", buf, sizeof(buf));
        printf((err != ESP_OK) ? "Failed to write NVS\n" : "NVS write done\n");
        // Close handle
        nvs_close(my_handle);
    }
}

void nvs_read(void)
{
    nvs_handle my_handle;
    esp_err_t err = nvs_open(STORAGE_NAMESPACE, NVS_READWRITE, &my_handle);
    if (err != ESP_OK) {
        printf("Error (%s) opening NVS handle!\n", esp_err_to_name(err));
    } else {
        // Read values including string, binary and integer
        int int_val;
        char str_val[20];
        size_t size = sizeof(str_val);
        uint8_t buf[4];
        err = nvs_get_i32(my_handle, "int_val", &int_val);
        err = nvs_get_str(my_handle, "string_val", str_val, &size);
        err = nvs_get_blob(my_handle, "blob_val", buf, &size);
        printf("int_val=%d, string_val=%s, blob_val=%02x%02x%02x%02x\n", int_val, str_val, buf[0], buf[1], buf[2], buf[3]);
        // Close handle
        nvs_close(my_handle);
    }
}

void app_main()
{
    // Initialize NVS
    esp_err_t err = nvs_flash_init();
    if (err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND) {
        // NVS partition was truncated and needs to be erased
        printf("NVS partition was truncated and needs to be erased\n");
        err = nvs_flash_erase();
        if (err != ESP_OK) {
            printf("Failed to erase NVS partition (%s)\n", esp_err_to_name(err));
            return;
        }
        // Retry nvs_flash_init
        err = nvs_flash_init();
    }
    if (err != ESP_OK) {
        printf("Failed to initialize NVS (%s)\n", esp_err_to_name(err));
        return;
    }
    // Write and read NVS values
    nvs_write();
    nvs_read();
}

此代码在ESP32上使用NVS Flash存储写入和读取值，并使用ESP-IDF开发框架进行编写。在使用此代码之前，应该先在ESP32上执行`nvs_flash_init()`进行初始化。