利用libxml2解析xml文档
C程序里可以利用libxml2库去解析xml文档。利用libxml2可以很轻松的解析，生成xml文件。
比较好的教程如下：http://www.blogjava.net/wxb_nudt/archive/2007/11/18/161340.html
这里演示一个小例子，包含了遍历节点，获取节点属性与值，以及获取CDATA里面的内容。
测验的xml文件：
<?xml version="1.0" encoding="utf-8"?>
<root name="test">
<content>
<pro id="moonApple"><![CDATA[<say>i still have lots to work on</say>]]></pro>
<details>
<detail name="dancing">like it</detail>
<detail name="singing">poor , just listen</detail>
<detail name="laugh"/>
<detail name="eating"><![CDATA[<food>candy</food>]]></detail>
</details>
</content>
</root>
test.c文件：
#include<stdio.h>
#include<string.h>
#include<libxml/parser.h>
#include<libxml/tree.h>
int parse_xml_file(char *buf,int len){
xmlDocPtr doc;
xmlNodePtr root,node,detail;
xmlChar *name,*value;
doc=xmlParseMemory(buf,len); //parse xml in memory
if(doc==NULL){
printf("doc == null\n");
return -1;
}
root=xmlDocGetRootElement(doc);
for(node=root->children;node;node=node->next){
if(xmlStrcasecmp(node->name,BAD_CAST"content")==0)
break;
}
if(node==NULL){
printf("no node = content\n");
return -1;
}
for(node=node->children;node;node=node->next){
if(xmlStrcasecmp(node->name,BAD_CAST"pro")==0){ //get pro node
name=xmlGetProp(node,BAD_CAST"id");
value=xmlNodeGetContent(node);
printf("this is %s:\n%s\n",(char*)name,(char*)value); //get value, CDATA is not parse and don't take into value
xmlFree(name);
xmlFree(value);
}else if(xmlStrcasecmp(node->name,BAD_CAST"details")==0){ //get details node
for(detail=node->children;detail;detail=detail->next){ //traverse detail node
if(xmlStrcasecmp(detail->name,BAD_CAST"detail")==0){
name=xmlGetProp(detail,BAD_CAST"name");
value=xmlNodeGetContent(detail);
if(strlen((char*)value)!=0){
printf("%s : %s\n",(char*)name,(char*)value);
}else{
printf("%s has no value\n",(char*)name);
}
xmlFree(name);
xmlFree(value);
}
}
}
}
xmlFreeDoc(doc);
return 0;
}
int main(void){
char *content;
unsigned long filesize;
FILE *file;
if((file=fopen("testxml","r"))==NULL){
perror("openf file error");
}
fseek(file,0,SEEK_END);
filesize=ftell(file);
rewind(file);
content=(char *)malloc(filesize+1);
memset(content,0,filesize+1);
fread(content,1,filesize,file);
fclose(file);
printf("content:\n%s\n",content);
if(parse_xml_file(content,filesize)<0){
perror("parse xml failed");
}
return 0;
}
输出结果：
this is moonApple: <say>i still have lots to work on</say> dancing : like it singing : poor , just listen laugh has no value eating : <food>candy</food>
这里主要关注XML文件里面的CDATA里面的内容~
更具体的使用方法和其他细节可以访问官网和上面的连接~