/**
* section: Tree
* synopsis: Navigates a tree to print element names
* purpose: Parse a file to a tree, use xmlDocGetRootElement() to
* get the root element, then walk the document and print
* all the element name in document order.
* usage: tree1 filename_or_URL
* test: tree1 test2.xml > tree1.tmp && diff tree1.tmp $(srcdir)/tree1.res
* author: Dodji Seketeli
* copy: see Copyright for the status of this software.
*/
#include <stdio.h>
#include <string.h>
#include <libxml/parser.h>
#include <libxml/tree.h> /*
*To compile this file using gcc you can type
* gcc `xml2-config --cflags --libs` -o tree1 tree1.c
*Run this program
* ./tree1 test.xml
*/ static const char* LEVELS[] = {"", " ", " ", " ", " ", " ", " ", " " }; static void printTree(xmlNode * a_node, int level); /**
* print_element_names:
* @a_node: the initial xml node to consider.
*
* 打印所有兄弟节点和子节点的名字.
*/
static void print_element_names(xmlNode * a_node, const char* msg); // 根据标签名称获取节点（可以实现更加复杂的逻辑，获取指定节点）
static xmlNode *getNode(xmlNode *rootNode, const char* tag, xmlNode **parentNode); // 删除当前节点，但是保留子节点
static void removeNode(xmlNode *parentNode, xmlNode *nodeToDelete); // 用一个父节点包装子节点
static void wrapWithNode(xmlNode *parentNode, xmlNode *node, xmlNode *newNode); // 增加一个新节点
static void appendNewChildNode(xmlNode *parentNode, xmlNode *newNode); /**
* print_element_names:
* @a_node: the initial xml node to consider.
*
* Prints the names of the all the xml elements
* that are siblings or children of a given xml node.
*/
static int test_removeNode(const char* filepath); /**
* print_element_names:
* @a_node: the initial xml node to consider.
*
* Prints the names of the all the xml elements
* that are siblings or children of a given xml node.
*/
static int test_wrapWithNode(const char* filepath); int main(int argc, char **argv)
{
if (argc != ) {
printf("error: invalid arguments");
return -;
} /*
* this initialize the library and check potential ABI mismatches
* between the version it was compiled for and the actual shared
* library used.
*/
LIBXML_TEST_VERSION printf("test: removeNode:\n");
test_removeNode(argv[]); printf("\n\ntest: wrapWithNode\n");
test_wrapWithNode(argv[]); /*
*Free the global variables that may
*have been allocated by the parser.
*/
xmlCleanupParser(); return ;
} void print_element_names(xmlNode * a_node, const char* msg)
{
xmlNode *cur_node = NULL; if (msg != NULL && strlen(msg) > ) {
printf("print: %s\n", msg);
} for (cur_node = a_node; cur_node; cur_node = cur_node->next) {
if (cur_node->type == XML_ELEMENT_NODE) {
printf("node type: Element, name: %s\n", cur_node->name);
} print_element_names(cur_node->children, "");
}
} void printTree(xmlNode * a_node, int level)
{
xmlNode *cur_node = NULL; //printf("%s", LEVELS[level]); for (cur_node = a_node; cur_node; cur_node = cur_node->next) {
if (cur_node->type == XML_ELEMENT_NODE) {
printf("%s%s <%d>\n", LEVELS[level], cur_node->name, cur_node->type);
printTree(cur_node->children, level + );
} else {
printf("%s#%s <%d>\n", LEVELS[level], cur_node->name, cur_node->type);
}
}
} xmlNode *getNode(xmlNode *rootNode, const char* tag, xmlNode **parentNode) {
xmlNode *cur = rootNode;
if ((cur->type == XML_ELEMENT_NODE) && (!xmlStrcmp(cur->name, (const xmlChar *)tag))){
*parentNode = NULL;
return cur;
} *parentNode = cur;
cur = cur->xmlChildrenNode;
while (cur != NULL) {
if ((cur->type == XML_ELEMENT_NODE) && (!xmlStrcmp(cur->name, (const xmlChar *)tag))){
return cur;
} if (cur->type == XML_ELEMENT_NODE) {
*parentNode = cur;
}
cur = cur->next;
} return NULL;
} // 删除当前节点，但是保留子节点
void removeNode(xmlNode *parentNode, xmlNode *nodeToDelete) {
if (nodeToDelete == NULL) {
printf("error: nodeToDelete is null");
return;
} xmlNodePtr siblingNode = nodeToDelete->next; while (siblingNode != NULL) {
if (siblingNode->type == XML_ELEMENT_NODE) {
printf("debug: found sibling: %s\n", siblingNode->name);
break;
} siblingNode = siblingNode->next;
} printf("debug: parentNode: %s, nodeToDelete: %s\n", parentNode->name, nodeToDelete->name);
printTree(parentNode, ); xmlNode *childrenNode = nodeToDelete->children;
if (childrenNode == NULL) {
printf("warn: childrenNode is null\n");
}
//xmlUnlinkNode(nodeToDelete->children); xmlNodePtr nextChildNode = NULL; while (childrenNode != NULL) {
printf("debug: childrenNode: %s\n", childrenNode->name);
nextChildNode = childrenNode->next;
xmlUnlinkNode(childrenNode); if (siblingNode != NULL) {
printf("debug: addPreSibling: %s, sibling is %s\n", childrenNode->name, siblingNode->name);
xmlAddPrevSibling(siblingNode, nextChildNode);
} else {
printf("debug: addChild: %s, parent is %s\n", childrenNode->name, parentNode->name);
printTree(childrenNode, );
xmlAddChild(parentNode, childrenNode);
} childrenNode = nextChildNode;
} xmlUnlinkNode(nodeToDelete);
xmlFreeNode(nodeToDelete);
} // 用一个父节点包装子节点
void wrapWithNode(xmlNode *parentNode, xmlNode *node, xmlNode *newNode) {
xmlUnlinkNode(node);
xmlAddChild(newNode, node);
xmlAddChild(parentNode, newNode);
} // 增加一个新节点
void appendNewChildNode(xmlNode *parentNode, xmlNode *newNode) {
xmlAddChild(parentNode, newNode);
} int test_removeNode(const char* filepath) {
xmlDoc *doc = NULL;
xmlNode *root_element = NULL;
xmlNode *parentNode = NULL;
xmlNode *curNode = NULL; /*parse the file and get the DOM */
doc = xmlReadFile(filepath, NULL, ); if (doc == NULL) {
printf("error: could not parse file %s\n", filepath);
} /*Get the root element node */
root_element = xmlDocGetRootElement(doc); // 删除节点，但是保留子节点
curNode = getNode(root_element, "p", &parentNode);
if (curNode == NULL) {
printf("error: p node is not found");
return -;
}
if (parentNode == NULL) {
// 根节点只能有一个子节点，这里就不处理了
printf("error: This is root node, should treat specially. root node should have only one node");
return -;
}
removeNode(parentNode, curNode); // 重新获取跟节点，应该是main了
root_element = xmlDocGetRootElement(doc); print_element_names(root_element, "after delete"); /*free the document */
xmlFreeDoc(doc);
return ;
} int test_wrapWithNode(const char* filepath) {
xmlDoc *doc = NULL;
xmlNode *root_element = NULL;
xmlNode *newNode = NULL; /*parse the file and get the DOM */
doc = xmlReadFile(filepath, NULL, ); if (doc == NULL) {
printf("error: could not parse file %s\n", filepath);
} /*Get the root element node */
root_element = xmlDocGetRootElement(doc); // 增加一个父节点,根节点需要特殊处理
xmlUnlinkNode(root_element);
newNode = xmlNewNode(NULL, BAD_CAST "main");
xmlAddChild(newNode, root_element);
xmlDocSetRootElement(doc, newNode);
// 重新获取跟节点，应该是main了
root_element = xmlDocGetRootElement(doc); print_element_names(root_element, "after wrap"); /*free the document */
xmlFreeDoc(doc); return ;
}
https://segmentfault.com/q/1010000000581732