Question

我按照此链接http://www.technical-recipes.com/2014/using-boostproperty_tree/来解析xml。但是如何在不指定特定键的情况下读取整个xml？我尝试了以下代码，但无法处理它，我收到的错误为No such node.

代码：

const std::string XML_PATH1 = "./test1.xml";
#define ROOTTAG  "roottag"
boost::property_tree::ptree pt1;
boost::property_tree::read_xml( XML_PATH1, pt1);
BOOST_FOREACH(boost::property_tree::ptree::value_type & node, pt1.get_child(ROOTTAG))
{
    std::string tagname = node.first;
    tagname += ".";
    boost::property_tree::ptree subtree = node.second;
    BOOST_FOREACH( boost::property_tree::ptree::value_type & v, subtree.get_child(node.first.data()))
    {
        //does not enter here
        tagname += v.first.data();
        tagname += ".";
        xmlmap[tagname] = tagvalue;
     }
}

必须在第二个循环中指定什么而不是node.first.data()？

BOOST_FOREACH( boost::property_tree::ptree::value_type & v, subtree.get_child(node.first.data()))

请注意，我必须使用BOOST_FOREACH本身并使用相同的方法。我引用了很多网站，但在没有指定特定密钥的情况下无法找到如何读取整个xml。

另外，如何使用上述方法读取多级xml？

Answer 1

当然，正如我在答案中所说的那样，整个“我想将其压平成地图”看起来是徒劳的。

c++ How to read XML using boost xml parser and store in map

然而，既然你似乎有意并且无法提出迭代迭代ptree的代码，那么这是一个开始：

<强> Live On Coliru

int main() {
    boost::property_tree::ptree pt;
    boost::property_tree::read_xml("test.xml", pt);

    Flat m;
    flatten(pt.get_child("roottag"), m, "DEMO");

    BOOST_FOREACH(Flat::value_type const& p, m) {
        std::cout << p.first << "\t= '" << p.second << "'\n";
    }
}

当你这样称呼时：

DEMO.billTo.<xmlattr>.country   = 'US'
DEMO.billTo.city    = 'Old Town'
DEMO.billTo.name    = 'Robert Smith'
DEMO.billTo.state   = 'PA'
DEMO.billTo.street  = '8 Oak Avenue'
DEMO.billTo.zip = '95819'
DEMO.comment    = 'Hurry, my lawn is going wild!'
DEMO.items.item.<xmlattr>.partNum   = '926-AA'
DEMO.items.item.USPrice = '39.98'
DEMO.items.item.comment = 'Confirm this is electric'
DEMO.items.item.productName = 'Baby Monitor'
DEMO.items.item.quantity    = '1'
DEMO.items.item.shipDate    = '1999-05-21'
DEMO.shipTo.<xmlattr>.country   = 'US'
DEMO.shipTo.city    = 'Mill Valley'
DEMO.shipTo.name    = 'Alice Smith'
DEMO.shipTo.state   = 'CA'
DEMO.shipTo.street  = '123 Maple Street'
DEMO.shipTo.zip = '90952'

打印例如。

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
  if ([segue.identifier isEqualToString:@"show"])
  {
   NSIndexPath *indexPath = [self.tableview indexPathForSelectedRow];
    if (_segement.selectedSegmentIndex == 0)
    {
    EventTableViewController *destViewController = segue.destinationViewController;
    destViewController.datais = [self.dataArray objectAtIndex:indexPath.row];
    _cellValue = destViewController.datais;
    }
  }
}

Second Tablviewcontroller FetchData Code:
-(void)addEventToCalendar
{
 NSArray *dir=NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
 NSString *dbpath=[NSString stringWithFormat:@"%@/Calendar1.sqlite",[dir lastObject]];
 sqlite3 *db;
if(sqlite3_open([dbpath UTF8String], &db)!=SQLITE_OK)
    return;
sqlite3_stmt *stmt;
NSString *select=[NSString stringWithFormat:@"select * from Events where EVENT_TYPE='%@'",cellValue];
const char *up=[select UTF8String];
if(sqlite3_prepare_v2(db, up, -1, &stmt, NULL)!=SQLITE_OK)
    return;

while (sqlite3_step(stmt)==SQLITE_ROW)
{
     NSNumber *eventsid=[NSNumber numberWithInt:(int)sqlite3_column_int(stmt,0)];
     NSString *eventname=[[NSString alloc]initWithUTF8String:(const char *)sqlite3_column_text(stmt, 1)];
     NSString *eventdate= [[NSString alloc]initWithUTF8String:(const char *)sqlite3_column_text(stmt, 2)];
     NSString *eventtype= [[NSString alloc]initWithUTF8String:(const char *)sqlite3_column_text(stmt, 3)];
     NSString *eventmonth= [[NSString alloc]initWithUTF8String:(const char *)sqlite3_column_text(stmt, 4)];
     NSString *eventstetus= [[NSString alloc]initWithUTF8String:(const char *)sqlite3_column_text(stmt, 5)];
     NSString *eid= [[NSString alloc]initWithUTF8String:(const char *)sqlite3_column_text(stmt, 6)];

    [_eventidArray addObject:eventsid];
    [_eventArray addObject:eventname];
    [_eventDateArray addObject:eventdate];
    [_eventstetusArray addObject:eventstetus];
    NSLog(@"%@ %@ %@",eventtype,eventmonth,eid);

 }

  sqlite3_finalize(stmt);
  sqlite3_close(db);

   NSLog(@"%@ name array in update",_eventArray);
   NSLog(@"%@ date array in upadte",_eventDateArray);
   NSLog(@"%@ name array in update",_eventidArray);
   NSLog(@"%@ date array in upadte",_eventstetusArray);
  }

使用boost读取xml

1 个答案: