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flashdb kvdb结构体参数存储问题

发布于 2024-05-18 10:19:48 浏览：1140 订阅该版

基于Flashdb的例程，添加一个结构体类型数据在default_kv表中；如下。
```c
struct index {
   uint8_t protocolVersion;
   char hardwareID[5];
};

static struct index index00;

/* default KV nodes */
static struct fdb_default_kv_node default_kv_table[] = {
        {"index", &index00, sizeof(index00)},
        {"username", "armink", 0}, /* string KV */
        {"boot_count", &boot_count, sizeof(boot_count)}, /* int type KV */
        {"boot_time", &boot_time, sizeof(boot_time)},    /* int array type KV */
```
然后在函数中使用fdb_kv_get_blob把数据保存在blob类型中，尝试打印出来。
```c
        /*default table测试代码：打印结构体*/
        struct STIndex_0x00 temp_index00;
        fdb_kv_get_blob(&kvdb, "index", fdb_blob_make(&blob, &temp_index00, sizeof(temp_index00)));
        if (blob.saved.len > 0) {
            FDB_INFO("get the 'index00' protocolVersion is: %d\n", temp_index00.protocolVersion);
            FDB_INFO("get the 'index00' hardwareID is: %s\n", temp_index00.hardwareID);
        }
/*default table测试代码：开机次数*/
        uint32_t temp_boot_count;
        fdb_kv_get_blob(&kvdb, "boot_count", fdb_blob_make(&blob, &temp_boot_count, sizeof(temp_boot_count)));
        if (blob.saved.len > 0) {
            FDB_INFO("get current boot count is: %d\n", temp_boot_count);
        }
```
别的像 string, int 和array等数据都能打印正常（输出台如下）， 但结构体好像没有储存正确。能帮忙看看具体哪里有错误吗？
```c
[FlashDB][kv][file] (../packages/FlashDB-latest/src/fdb_kvdb.c:1638) KVDB size is 1048576 bytes.
[FlashDB][FDB] get the username value is: armink
[FlashDB][FDB] get first time is: 0
[FlashDB][FDB] get second time is: 1
 [FlashDB][FDB] get current boot count is: 41
[FlashDB][sample][kvdb][basic] ==================== kvdb_basic_sample =========
[FlashDB][sample][kvdb][basic] get the 'boot_count' value is 41
[FlashDB][sample][kvdb][basic] set the 'boot_count' value to 42
[FlashDB][sample][kvdb][basic]==================================================
```