• iOS 中的XML解析代码(SAX)


    1、XML解析(SAX)

    NSXMLParser SAX 大文件

    1)打开文档

    - (void)parserDidStartDocument:(NSXMLParser *)parser
    

    2)开始查找起始标签

    - (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary<NSString *,NSString *> *)attributeDict
    
    开始元素 : elementName
    元素属性 : attributeDict
    

    3)获取标签内容

    - (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string 
    
    获取内容 : string
    

    4)查找结束标签

    - (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
    
    结束元素 : elementName namespaceURI 和 qName 为空值
    

    5)关闭文档(查询结束)

    
    - (void)parserDidEndDocument:(NSXMLParser *)parser
    

    实现原理:

    • 1.在查找起始标签的时候,判断elementName是否与对应的字符串相等,并将接收到的内容删除

    • 2.因为获取内容的时候会出现获取两次 则使用追加方法,防止多次执行获取内容的方法 string + @“ "

    • 3.在查找结束标签的时候,判断elementName是否与对应的字符串相等,并将获取的模型加载到可变数组中,作为数据源,进行其他操作,再判断是否与对应的字符串不相等,利用kvc将对应的结束标签作为KEY值,对应获取的内容作为value值

    //
    //  ViewController.m
    //  
    //
    //  Created by peng on 16/2/19.
    //  Copyright (c) 2016年 pss. All rights reserved.
    //
    
    #import "ViewController.h"
    #import "PSSTrainInfo.h"
    
    static NSString *identifier = @"cellID";
    
    @interface ViewController ()<UITableViewDataSource, UITableViewDelegate, NSXMLParserDelegate>
    
    @property (nonatomic, strong) UITableView *tableView;
    
    @property (nonatomic, strong) NSMutableArray *dataList;
    
    @property (nonatomic, strong) PSSTrainInfo *model;
    
    @property (nonatomic, strong) NSMutableString *muString;
    
    @end
    
    @implementation ViewController
    
    - (UITableView *)tableView {
        
        if (!_tableView) {
            _tableView = [[UITableView alloc] initWithFrame:self.view.bounds style:UITableViewStylePlain];
            
            _tableView.delegate = self;
            _tableView.dataSource = self;
            
        }
        return _tableView;
    }
    
    - (NSMutableString *)muString {
        
        if (!_muString) {
            _muString = [NSMutableString string];
        }
        return _muString;
    }
    
    - (NSMutableArray *)dataList {
        
        if (!_dataList) {
            _dataList = [NSMutableArray array];
        }
        return _dataList;
    }
    
    - (PSSTrainInfo *)model {
        
        if (!_model) {
            _model = [[PSSTrainInfo alloc] init];
        }
        return _model;
    }
    
    - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
        
        return self.dataList.count;
    }
    
    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
        
        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:identifier];
        
        if (!cell) {
            cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:identifier];
        }
        
        
        
        return cell;
    }
    
    - (void)parserDidStartDocument:(NSXMLParser *)parser  {
        
        NSLog(@"开始解析");
        
    }
    
    - (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary<NSString *,NSString *> *)attributeDict {
        
        NSLog(@"起始元素:%@", elementName);
        
        if ([elementName isEqualToString:@"trainDetailInfo"]) {
            
            [self.model setValuesForKeysWithDictionary:attributeDict];
            
        }
        self.muString = nil;
    }
    
    - (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string {
        
        NSLog(@"内容:%@", string);
        
        [self.muString appendString:string];
        
    }
    
    - (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName {
        
        NSLog(@"结束元素:%@", elementName);
        
        if ([elementName isEqualToString:@"trainDetailInfo"]) {
            
            [self.dataList addObject:self.model];
            
        }else if (![elementName isEqualToString:@"dataSet"] && ![elementName isEqualToString:@"diffgr:diffgram"]) {
            
            [self.model setValue:self.muString forKey:elementName];
            
        }
        
        
        
    }
    
    - (void)parserDidEndDocument:(NSXMLParser *)parser {
        
        NSLog(@"结束解析");
        
        [self.tableView reloadData];
        
        NSLog(@"%@",self.dataList);
        
    }
    
    - (void)viewDidLoad
    {
        [super viewDidLoad];
    
        NSURL *url = [NSURL URLWithString:@"http://192.168.1.2/train.xml"];
        
        NSURLRequest *request = [NSURLRequest requestWithURL:url cachePolicy:0 timeoutInterval:15];
        
        [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _Nullable connectionError) {
           
            
            NSXMLParser *parser = [[NSXMLParser alloc] initWithData:data];
            
            parser.delegate = self;
            
            [parser parse];
            
            
        }];
        
        [self.view addSubview:self.tableView];
        
    }
    - (void)didReceiveMemoryWarning
    {
        [super didReceiveMemoryWarning];
        // Dispose of any resources that can be recreated.
    }
    
    @end
    
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  • 原文地址:https://www.cnblogs.com/PSSSCode/p/5295292.html
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