minixml3.1库的使用

大家好，这几天我使用minixml 3.1库解析了xml格式数据，由于是头一次使用，且时间比较紧，总结的比较简陋。

libmxml.so解析xml数据时的内存布局如下图，以下面简单例子说明：

加载方式为：mxmlLoadString(NULL, pacData, MXML_OPAQUE_CALLBACK);

采用 MXML_OPAQUE_CALLBACK方式，跟采用MXML_NO_CALLBACK、MXML_TEXT_CALLBACK方式是不一样的

 

解析xml代码如下：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <iconv.h>
#include "mxml.h"

#define EL_RESP               "Response"
#define EL_CMDTYPE            "CmdType"
#define EL_NAME               "Name"
#define EL_DEVICEID           "DeviceID"

int parsexml(char *pacData)
{
    mxml_node_t *root = mxmlLoadString(NULL, pacData, MXML_OPAQUE_CALLBACK);
    mxml_node_t    *resp = mxmlFindElement(root, root, EL_RESP, NULL, NULL, MXML_DESCEND_FIRST);
    mxml_node_t    *node = NULL;
    char* pkey[] = { EL_CMDTYPE, EL_NAME, EL_DEVICEID };
    int i = 0, icount =sizeof(pkey) / sizeof(pkey[0]);
    node = mxmlFindElement(resp, root, pkey[0], NULL, NULL, MXML_DESCEND_FIRST);
    for(; i < icount; i++)
    {
        mxml_node_t* child = mxmlGetFirstChild(node);
        const char* pvalue = mxmlGetOpaque(node);
        const char* pvalue1 = mxmlGetOpaque(child);
        printf("*** %d. %s:[%s] [%s]\n", i+1, pkey[i], pvalue, pvalue1);
        node = mxmlFindElement(node, root, pkey[i + 1], NULL, NULL, MXML_NO_DESCEND);
    }
    
    return 0;
}

int main(int argc, char* argv[])
{
    char *cfgpath = "./ljt.xml";
    FILE* pfile = fopen(cfgpath, "r");
    if(NULL == pfile)
    {
        printf("*** failed to open file %s\n", cfgpath);
        return 0;
    }
    char acData[1500] = { 0 };
    fseek(pfile, 0, SEEK_END);
    long long llsize = ftell(pfile);
    fseek(pfile, 0, SEEK_SET);
    fread(acData, llsize, 1, pfile);
    fclose(pfile);
    printf("*** filesize = %lld\n", llsize);
    printf("%s\n", acData);
    
    parsexml(acData);

    return 0;
}

 

20231202补加

生成如下结构mxl

 生成xml代码如下：

#include <stdlib.h>
#include <stdio.h>
#include "mxml.h"

int main(int argc, char* argv[])
{
    mxml_node_t *pxml = NULL, *pResp = NULL;
    pxml = mxmlNewXML("1.0");
    pResp = mxmlNewElement(pxml, "Response");
    //CmdType
    mxml_node_t *cmdType = mxmlNewElement(pResp, "CmdType");
    mxmlNewText(cmdType, 0, "QueryList");
    //SN
    mxml_node_t *sn = mxmlNewElement(pResp, "SN");
    mxmlNewText(sn, 0, "9527");
    //ID
    mxml_node_t *id = mxmlNewElement(pResp, "ID");
    mxmlNewText(id, 0, "51201000000");
    //NodeList
    mxml_node_t *nodelist = mxmlNewElement(pResp, "NodeList");
    mxmlElementSetAttr(nodelist, "Num", "3");

    mxml_node_t *item = NULL, *name = NULL, *level = NULL;
    //NodeList-item   1
    item = mxmlNewElement(nodelist, "item");
    //NodeList-item-ID
    id = mxmlNewElement(item, "ID");
    mxmlNewText(id, 0, "11100010002");
    //NodeList-item-Name
    name = mxmlNewElement(item, "Name");
    mxmlNewText(name, 0, "张三");
    //NodeList-item-Level
    level = mxmlNewElement(item, "Level");
    mxmlNewInteger(level, 11);
    
    //NodeList-item    2
    item = mxmlNewElement(nodelist, "item");
    //NodeList-item-ID
    id = mxmlNewElement(item, "ID");
    mxmlNewText(id, 0, "11100010003");
    //NodeList-item-Name
    name = mxmlNewElement(item, "Name");
    mxmlNewText(name, 0, "李四");
    //NodeList-item-Level
    level = mxmlNewElement(item, "Level");
    mxmlNewInteger(level, 12);
    
    const char* numVal = mxmlElementGetAttr(nodelist, "Num");
    printf("old node [NodeList] Num=[%s]\n", numVal);
    mxmlElementSetAttr(nodelist, "Num", "2");
    numVal = mxmlElementGetAttr(nodelist, "Num");
    printf("new node [NodeList] Num=[%s]\n", numVal);
    
    
    mxml_node_t *temp = mxmlFindElement(pxml, pxml, "NodeList", NULL ,NULL, MXML_DESCEND);
    if(NULL != temp)
    {
        const char* pname = mxmlGetElement(temp);
        const char* pvalue = mxmlGetOpaque(temp);
        printf("*** element name = [%s] value = [%s]\n", pname, pvalue);
    }
    else
    {
        printf("*** no find element [%s]\n", "NodeList");
    }
    char buff[1024];
    bzero(buff, sizeof(buff));
    mxmlSaveString(pxml, buff, sizeof(buff), MXML_NO_CALLBACK);
    printf("*** new xml:\n%s\n", buff);

    FILE* fp = fopen("./mytest.xml", "w");
    mxmlSaveFile(pxml, fp, MXML_NO_CALLBACK);
    fclose(fp);
    mxmlDelete(pxml);

    return 0;
}