给定一段的html文本,用C++求宽度和高度
时间: 2024-05-10 08:17:39 浏览: 13
可以使用第三方库libxml2解析html文本,获取相关信息,然后使用对应的库计算宽度和高度。
以下是使用libxml2和cairo库计算html文本宽度和高度的示例代码:
```c++
#include <iostream>
#include <libxml/HTMLparser.h>
#include <cairo.h>
void calculate_size(xmlNode *node, cairo_t *cr, double &width, double &height) {
if (node == NULL) {
return;
}
if (xmlStrcmp(node->name, (const xmlChar *)"br") == 0) {
// 换行
cairo_show_text(cr, "\n");
cairo_text_extents_t extents;
cairo_text_extents(cr, "\n", &extents);
width = 0;
height += extents.height;
} else if (node->type == XML_TEXT_NODE) {
// 文本节点
cairo_text_extents_t extents;
cairo_text_extents(cr, (const char *)node->content, &extents);
width += extents.width;
height += extents.height;
cairo_show_text(cr, (const char *)node->content);
} else {
// 其他节点
xmlNode *cur_node = node->children;
while (cur_node != NULL) {
calculate_size(cur_node, cr, width, height);
cur_node = cur_node->next;
}
}
}
int main() {
// 解析html
const char *html = "<html><head></head><body><p>Hello, world!</p></body></html>";
htmlDocPtr doc = htmlReadMemory(html, strlen(html), NULL, NULL, HTML_PARSE_RECOVER | HTML_PARSE_NOERROR | HTML_PARSE_NOWARNING);
if (doc == NULL) {
std::cerr << "Failed to parse html.\n";
return 1;
}
// 绘制
cairo_surface_t *surface = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, 0, 0);
cairo_t *cr = cairo_create(surface);
cairo_select_font_face(cr, "Sans", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_NORMAL);
cairo_set_font_size(cr, 12.0);
xmlNode *root_element = xmlDocGetRootElement(doc);
double width = 0, height = 0;
calculate_size(root_element, cr, width, height);
// 输出
std::cout << "Width: " << width << std::endl;
std::cout << "Height: " << height << std::endl;
// 释放资源
cairo_destroy(cr);
cairo_surface_destroy(surface);
xmlFreeDoc(doc);
xmlCleanupParser();
return 0;
}
```
需要注意的是,这个示例只能计算简单的html文本,对于复杂的html文本可能无法正确计算宽度和高度。