107-ESP32_SDK开发-flash数据存储nvs

说明

nvs是底层封装的一套把数据存储到flash里面的函数;

数据是以键值对的形式存储数据(就是标识符+数据的形式)

不如直接看代码

#include <stdio.h>
#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "nvs_flash.h"
#include "esp_log.h"


void app_main(void)
{
    //初始化 NVS
    esp_err_t err = nvs_flash_init();
    if (err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND) {
      ESP_ERROR_CHECK(nvs_flash_erase());
      err = nvs_flash_init();
    }
    ESP_ERROR_CHECK(err);


    /*操作nvs时用的句柄*/
    nvs_handle_t my_handle;

    /*打开*/     //操作的表格名字 //以读写模式打开
    err = nvs_open("storage", NVS_READWRITE, &my_handle);

    /*写*/
    err = nvs_set_i32(my_handle, "test", 111);
    /*提交*/
    err = nvs_commit(my_handle);

    int32_t test_value;
    /*读*/
    err = nvs_get_i32(my_handle, "test", &test_value);
    printf("test_value = %d\n", test_value);

    /*关闭*/
    nvs_close(my_handle);
}