关于XML,有两种解析方式,分别是SAX(Simple API for XML,基于事件驱动的解析方式,逐行解析数据,采用协议回调机制)和DOM(Document Object Model ,文档对象模型。解析时需要将XML文件整体读入,并且将XML结构化成树状,使用时再通过树状结构读取相关数据,查找特定节点,然后对节点进行读或写)。苹果官方原生的NSXMLParse类库采用第一种方式,即SAX方式解析XML,它基于事件通知的模式,一边读取文档一边解析数据,不用等待文档全部读入以后再解析,所以如果你正打印解析的数据,而解析过程中间出现了错误,那么在错误节点之间的数据会正常打印,错误后面的数据不会被打印。解析过程由NSXMLParserDelegate协议方法回调。
首先先创建一个xml文件就叫做xml.xml吧:
<?xml version="1.0" encoding="UTF-8"?> <Root> <Student> <pid>1</pid> <name>Jack</name> <sex>Male</sex> <age>18</age> </Student> <Student> <pid>2</pid> <name>Jodan</name> <sex>Male</sex> <age>19</age> </Student> <Student> <pid>3</pid> <name>Mily</name> <sex>Female</sex> <age>18</age> </Student> <Student> <pid>4</pid> <name>Rena</name> <sex>Female</sex> <age>20</age> </Student> <Student> <pid>5</pid> <name>Amy</name> <sex>Female</sex> <age>22</age> </Student> <Student> <pid>6</pid> <name>Teresa</name> <sex>Female</sex> <age>20</age> </Student> </Root>
接首创建一个相对应的M
//Person.h #import <Foundation/Foundation.h> @interface Person : NSObject @property (nonatomic,copy) NSString *pid; @property (nonatomic,copy) NSString *name; @property (nonatomic,copy) NSString *sex; @property (nonatomic,copy) NSString *age; @end //Person.m #import "Person.h" @implementation Person @synthesize pid,name,age,sex; @end
接着添加一个自定义UITableViewCell类就让它叫做CustomTableViewCell.m吧,下一步将用到,代码如下:
//CustomTableViewCell.h #import <UIKit/UIKit.h> @interface CustomTableViewCell : UITableViewCell @property UILabel *lblName; @property UILabel *lblSex; @property UILabel *lblAge; @end //CustomTableViewCell.m #import "CustomTableViewCell.h" @implementation CustomTableViewCell @synthesize lblAge,lblName,lblSex; - (void)awakeFromNib { // Initialization code } - (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier { self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]; if (self) { UILabel *titleOfNameLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 10, 60, 20)]; titleOfNameLabel.text = @"姓名:"; UILabel *titleOfAgeLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 40, 60, 20)]; titleOfAgeLabel.text = @"年龄:"; UILabel *titleOfSexLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 70, 60, 20)]; titleOfSexLabel.text = @"性别:"; //titleOfNameLabel.backgroundColor = [UIColor blackColor]; [self addSubview:titleOfNameLabel]; [self addSubview:titleOfAgeLabel]; [self addSubview:titleOfSexLabel]; lblName = [[UILabel alloc] initWithFrame:CGRectMake(80, 10, 100, 20)]; lblAge = [[UILabel alloc] initWithFrame:CGRectMake(80, 40, 100, 20)]; lblSex = [[UILabel alloc] initWithFrame:CGRectMake(80, 70, 100, 20)]; [self addSubview:lblName]; [self addSubview:lblAge]; [self addSubview:lblSex]; } return self; } - (void)setSelected:(BOOL)selected animated:(BOOL)animated { [super setSelected:selected animated:animated]; // Configure the view for the selected state } @end
在storyboard内添加一个ViewController并加一个TableView并设置好相应的约束条件后添加一个继承自UIViewController的类估且就叫做XmlToTableViewController,并设置上一步在storyboard添加的ViewController的Customer Class为XmlToTableViewController。
XmlToTableViewController要实现NSXMLParserDelegate这个接口,并选择相应要实现的方法。
1 //XmlToTableViewController.h 2 #import "ViewController.h" 3 #import "Person.h" 4 5 @interface XmlToTableViewController : ViewController 6 7 @property (weak, nonatomic) IBOutlet UITableView *tableView; 8 9 @property (nonatomic,strong) NSXMLParser *parser; 10 @property (nonatomic,strong) NSMutableArray *personArray; 11 @property (nonatomic,copy) NSString *currentElement; 12 @property (nonatomic,strong) Person *person; 13 14 @end 15 16 17 //XmlToTableViewController.m 18 #import "XmlToTableViewController.h" 19 #import "CustomTableViewCell.h" 20 21 @interface XmlToTableViewController () <UITableViewDataSource,UITableViewDelegate,NSXMLParserDelegate> 22 23 @end 24 25 @implementation XmlToTableViewController 26 27 - (void)viewDidLoad { 28 [super viewDidLoad]; 29 30 dispatch_queue_t q1 = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0); 31 32 dispatch_async(q1, ^{ 33 34 35 }); 36 37 NSBundle *bundle = [NSBundle mainBundle]; 38 NSString *path = [bundle pathForResource:@"xml" ofType:@"xml"]; 39 NSData *data = [NSData dataWithContentsOfFile:path]; 40 self.parser = [[NSXMLParser alloc] initWithData:data]; 41 //添加代理 42 self.parser.delegate = self; 43 self.personArray = [NSMutableArray arrayWithCapacity:5]; 44 [self.parser parse]; 45 46 self.tableView.delegate = self; 47 self.tableView.dataSource = self; 48 } 49 50 51 52 //几个代理方法的实现,是按逻辑上的顺序排列的,但实际调用过程中中间三个可能因为循环等问题乱掉顺序 53 //开始解析 54 - (void)parserDidStartDocument:(NSXMLParser *)parser { 55 NSLog(@"parserDidStartDocument"); 56 } 57 58 -(void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary<NSString *,NSString *> *)attributeDict { 59 self.currentElement = elementName; 60 if([self.currentElement isEqualToString:@"Student"]) { 61 self.person = [[Person alloc] init]; 62 } 63 } 64 65 //获取节点内容 66 -(void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string { 67 if ([self.currentElement isEqualToString:@"pid"]) { 68 [self.person setPid:string]; 69 } else if([self.currentElement isEqualToString:@"name"]) { 70 [self.person setName:string]; 71 } else if([self.currentElement isEqualToString:@"sex"]) { 72 [self.person setSex:string]; 73 } else if([self.currentElement isEqualToString:@"age"]) { 74 [self.person setAge:string]; 75 } 76 } 77 78 //当一个节点读取完成后 79 -(void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName { 80 if([elementName isEqualToString:@"Student"]) { 81 [self.personArray addObject:self.person]; 82 } 83 self.currentElement = nil; 84 } 85 86 //完成XML文件的读取 87 -(void)parserDidEndDocument:(NSXMLParser *)parser { 88 NSLog(@"parserDidEndDocument"); 89 NSLog(@"Student's count is %lu",(unsigned long)[self.personArray count]); 90 [self.tableView reloadData]; 91 } 92 93 94 //MARK:TABLEVIEW 95 - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { 96 return [self.personArray count]; 97 } 98 99 - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { 100 NSString *idenfifier = @"Cell"; 101 //PersoUITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:idenfifier]; 102 CustomTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:idenfifier]; 103 if (cell == nil) { 104 //用xib文件先画好 105 /*cell = [[[NSBundle mainBundle] loadNibNamed:@"PersonUITableViewCell" owner:nil options:nil] firstObject]; 106 Person *currentPerson = [self.personArray objectAtIndex:indexPath.row]; 107 if (currentPerson) { 108 cell.lblName.text = currentPerson.name; 109 cell.lblAge.text = currentPerson.age; 110 cell.lblId.text = currentPerson.pid; 111 cell.lblSex.text = currentPerson.sex; 112 }*/ 113 114 cell = [[CustomTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:idenfifier]; 115 116 [tableView registerClass:[CustomTableViewCell class] forCellReuseIdentifier:idenfifier]; 117 } 118 Person *currentPerson = [self.personArray objectAtIndex:indexPath.row]; 119 if (currentPerson) { 120 cell.lblName.text = currentPerson.name; 121 cell.lblAge.text = currentPerson.age; 122 cell.lblSex.text = currentPerson.sex; 123 } 124 125 return cell; 126 } 127 128 - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath { 129 return 126; 130 }
最终的效果: