实战知识点和错误

知识点：

1.

//字体居中

cell.textLabel.textAlignment = UITextAlignmentCenter;

 

设置字体

cell.textLabel.font = [UIFontsystemFontOfSize:16]; 

 

//切换场景

presentModalViewController

对应

[self dismissModalViewControllerAnimated:YES]

 

pushViewController

对应

[self.navigationControllerpopViewControllerAnimated:YES];

 

 

//位置大小

UIImageView:

backgroundViewMid.frame.size.height 是这个UIImageView的高度

backgroundViewMid.frame.size.width  是这个UIImageView的宽度

backgroundViewMid.frame.origin.x    是这个UIImageView的x位置

backgroundViewMid.frame.origin.y    是这个UIImageView的y位置

 

2. 

UITableView:   新建cell.textLabel.text不能控制其长度 需要新建一个UILabel

    UILabel: 在xib中建立了UILabel 设定了frame的位置  在程序中没法再设置 必须自己手动建立一个UILabel

 

3.

tableviewcell不可选中（但是要是上面放按钮也不能点）

cell.userInteractionEnabled = NO; 

 

//cell设置为不可选 放按钮可点

cell.selectionStyle = UITableViewCellSelectionStyleNone;

 

//选中后的背景框颜色即刻消失

[tableView deselectRowAtIndexPath:indexPath animated:YES];

 

 

4.写数据

//获得所有的学科

+(NSArray*) allSubjects

{

    NSMutableArray* subjectArray = [NSMutableArrayarray];

    NSMutableDictionary* subjectDict = nil;

    

    subjectDict = [NSMutableDictionary dictionary];

    [subjectDict setObject:@"自然学科" forKey:@"name"];

    [subjectDict setObject:@"1" forKey:@"id"];

    [subjectArray addObject:subjectDict];

    

    subjectDict = [NSMutableDictionary dictionary];

    [subjectDict setObject:@"人文社会" forKey:@"name"];

    [subjectDict setObject:@"2" forKey:@"id"];

    [subjectArray addObject:subjectDict];

 

    subjectDict = [NSMutableDictionary dictionary];

    [subjectDict setObject:@"工程设计" forKey:@"name"];

    [subjectDict setObject:@"3" forKey:@"id"];

    [subjectArray addObject:subjectDict];

 

    

    subjectDict = [NSMutableDictionary dictionary];

    [subjectDict setObject:@"农业医药" forKey:@"name"];

    [subjectDict setObject:@"4" forKey:@"id"];

    [subjectArray addObject:subjectDict];

 

    return subjectArray;

}

 

//获得更新包

-(NSMutableDictionary*) allEntryData

{

    NSMutableDictionary* subjectDict = [NSMutableDictionarydictionary];

    NSMutableArray* subjectArray = nil;

    

    subjectArray = [[[NSMutableArray alloc] init] autorelease];

    [subjectArray addObject:@"2012年8月30日天文学更新包"];

    [subjectDict setObject:subjectArray forKey:@"A"];

    

    subjectArray = [[[NSMutableArray alloc] init] autorelease];

    [subjectArray addObject:@"2012年8月35日人文社会学更新包"];

    [subjectDict setObject:subjectArray forKey:@"B"];

    

    return subjectDict;

}

 

5.

设置UIButton上字体的颜色，不是用：

    [payWayButton.titleLabelsetTextColor:[UIColorblackColor]];

 而是用：

 [payWayButtonsetTitleColor:[UIColorblackColor] forState:UIControlStateNormal];

 

6.

    int iSection = 0;

    

    iSection += 1;

    subjectArray = [[[NSMutableArray alloc] init] autorelease];

    [subjectArray addObject:@"2012年8月30日天文学更新包"];

    [subjectDict setObject:subjectArray forKey:[NSString stringWithFormat:[NSString stringWithFormat:@"%d", iSection], nil]];

 

7.tableview自己画线对齐要注意分割线不能去掉只能把颜色清空

不能用 这个是去掉tableview自己画线 就不会自动对齐

gradeTwoTableView.separatorStyle = UITableViewCellSeparatorStyleNone; 

 

要用 这个只是去掉分割线颜色还会自动对齐

gradeTwoTableView.separatorColor = [UIColorclearColor];

 

 

7.post请求

//    NSString *post = [NSString stringWithFormat:nil, 4, opinionTextView.text];

//    NSData *postData=[post dataUsingEncoding:NSUTF8StringEncoding];

//    NSMutableURLRequest *connectionRequest = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:nil]];

//    [connectionRequest setHTTPMethod:@"POST"];

//    [connectionRequest setTimeoutInterval:100.0];

//    [connectionRequest setCachePolicy:NSURLRequestUseProtocolCachePolicy];

//    [connectionRequest setHTTPBody:postData];

//    

//    //输出数据

//    NSData *data=[NSURLConnection sendSynchronousRequest:connectionRequest returningResponse:nil error:nil];

//    NSString *stringdata=[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];

//    NSLog(@"%@", stringdata);

    

    NSString *post = @"name=admin&password=123456";

    NSData *postData=[post dataUsingEncoding:NSUTF8StringEncoding];

    NSMutableURLRequest *connectionRequest = [NSMutableURLRequest

                                              requestWithURL:[NSURL URLWithString:@"http://127.0.0.1/test/test.php"]];

    [connectionRequest setHTTPMethod:@"POST"];

    [connectionRequest setTimeoutInterval:100.0];

    [connectionRequest setCachePolicy:NSURLRequestUseProtocolCachePolicy];

    [connectionRequest setHTTPBody:postData];

    NSData *data=[NSURLConnectionsendSynchronousRequest:connectionRequest returningResponse:nilerror:nil];

    NSString *stringdata=[[NSStringalloc] initWithData:data encoding:NSUTF8StringEncoding];

    NSLog(@"~~~~~%@~~~~",stringdata);

 

 

 

 

 

 

 

//去掉空格

NSString* isRightWord = [ageTextField.textstringByTrimmingCharactersInSet:[NSCharacterSetwhitespaceCharacterSet] ];

if (isRightWord == nil || [@"" isEqualToString:isRightWord])

{

UIAlertView *alert = [[UIAlertViewalloc] initWithTitle:@""message:@"年龄不能为空!" delegate:selfcancelButtonTitle:@"确定"otherButtonTitles:nil, nil];

    [alert show];

    [alert release];

    return;            

}

 

1、判断用户名，在2－16位

-(BOOL)CheckInput:(NSString *)_text

{ 

    NSString *Regex = @"^\\w{2,16}$";

    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", Regex]; 

    return [emailTest evaluateWithObject:_text]; 

}

 

2、判断手机号码，1开头的十一位数字 

-(BOOL)CheckInput:(NSString *)_text

{ 

    NSString *Regex = @"1\\d{10}"; 

    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", Regex];

    return [emailTest evaluateWithObject:_text]; 

}

 

3、判断邮箱

-(BOOL)CheckInput:(NSString *)_text 

{ 

    NSString *Regex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";

    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", Regex]; 

    return [emailTest evaluateWithObject:_text]; 

}

 

4、判断密码，6－16位

 -(BOOL)CheckInput:(NSString *)_text

{

    NSString *Regex = @"\\w{6,16}";

    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", Regex];

    return [emailTest evaluateWithObject:_text];

}

 

5、判断是否为整型
- (BOOL)isPureInt:(NSString *)string{
NSScanner* scan = [NSScanner scannerWithString:string];
int val;  
return [scan scanInt:&val] && [scan isAtEnd];
}

6、判断是否为浮点型
- (BOOL)isPureFloat:(NSString *)string{
NSScanner* scan = [NSScanner scannerWithString:string];
float val;
return [scan scanFloat:&val] && [scan isAtEnd];

 

 

 

 

 

 

 

 

 

 

 

 

1。

Undefined symbols for architecture i386:

  "_OBJC_CLASS_$_EGORefreshTableHeaderView", referenced from:

      objc-class-ref in CategoryGradeTwo.o

ld: symbol(s) not found for architecture i386

clang: error: linker command failed with exit code 1 (use -v to see invocation)

 

需要加framework 如果还有错误  就点击 报错的类 再把右上角 target membership里的勾打上

 

 

2.

format string is not a string literal (potentially insecure)     

加个nil既可解决   

[selfhudLabelText:[NSStringstringWithFormat:sError.error,nil]];

 

3.

xcode 升级到了 4.5 之后 只要往xib上面拖放控件 就会报错,

解决方法, 选中当前的 xib文件,

再右边的 inspector 一栏 将 interface builder document 下的 use autolayout 复选框去掉就可以了

VIA:http://www.lazyid.com/2012/07/04/could-not-instantiate-class-named-nslayoutconstraint/comment-page-1/