簡單的判斷用戶名，密碼，確認密碼，手機號碼，驗證碼為空，輸入信息含空格，密碼不一致

#pragma mark--判斷輸入內容
-(BOOL)isNULL{
    
    //設置判斷值
    BOOL result = YES;
    //警示框內容
    NSString* msg = @"";
    //判斷內容
    if (self.register_userNameTF.text.length == 0) {
        //為空時  判斷值為NO
        result = NO;
        msg = @"用戶名為空";
    }else  if (self.register_userPwdTF.text.length == 0) {
        //為空時  判斷值為NO
        result = NO;
        msg = @"密碼為空";
    }else if (self.register_surePwdTF.text.length == 0) {
        //為空時  判斷值為NO
        result = NO;
        msg = @"確認密碼為空";
    }else if (self.register_phoneNumberTF.text.length == 0) {
        //為空時  判斷值為NO
        result = NO;
        msg = @"手機號碼為空";
    }else if (self.register_verificationCodeTF.text.length == 0) {
        //為空時  判斷值為NO
        result = NO;
        msg = @"驗證碼為空";
    }else if ([self.register_userNameTF.text containsString:@" "] || [self.register_userPwdTF.text containsString:@" "] || [self.register_surePwdTF.text containsString:@" "] || [self.register_phoneNumberTF.text containsString:@" "] || [self.register_verificationCodeTF.text containsString:@" "] ) {
        //輸入帶有空格時  判斷值為NO
        result = NO;
        msg = @"輸入含有空格為空";
    }else if (![self.register_userPwdTF.text isEqualToString:self.register_surePwdTF.text]) {
        //密碼與確認密碼不一致 判斷值為NO
        result = NO;
        msg = @"密碼不一致";
    }
    
    //判斷值
    if (result) {
        //若為YES，直接返回
        return result;
    }else{
        //調用彈出方法
        [self alertWithMsg:msg];
        return result;
    }
}

1.以警示框形式彈出

#pragma mark--警示框
-(void) alertWithMsg:(NSString*)msg{
    
    //初始化AlertController11
    UIAlertController* alertC = [UIAlertController alertControllerWithTitle:@"友情提示" message:msg preferredStyle:(UIAlertControllerStyleAlert)];
    //設置確認按鈕組件方法
    UIAlertAction* alertAction = [UIAlertAction actionWithTitle:@"確認" style:(UIAlertActionStyleCancel) handler:^(UIAlertAction * _Nonnull action){
        
        NSLog(@"點擊確認");
    }];
    //添加確認按鈕組件
    [alertC addAction:alertAction];
    //模態彈出警示框
    [self presentViewController:alertC animated:YES completion:nil];
    
}

2.以提醒框形式彈出

導入
#import "MBProgressHUD.h"http://提示框
屬性
@property (nonatomic,strong) MBProgressHUD* toastView;//彈出提示
懶加載
#pragma mark--懶加載
-(MBProgressHUD*) toastView{
    
    if (!_toastView) {
        _toastView = [MBProgressHUD showHUDAddedTo:self.view animated:YES];
        _toastView.minShowTime = 2;
        [_toastView setMode:MBProgressHUDModeText];
        _toastView.contentColor = [UIColor grayColor];
        _toastView.bezelView.backgroundColor = [UIColor blackColor];
    }
    return _toastView;
}

提醒框方法
#pragma mark--提示框
-(void) alertWithMsg:(NSString*)msg{
    
    self.toastView.label.text =msg;
    [self.toastView hideAnimated:YES];
    //隱藏掉之后回執行的block
    UserInfoVC* vc_self = self;
    self.toastView.completionBlock = ^{
        
        [vc_self.toastView removeFromSuperview];
        vc_self.toastView = nil;
    };
    
}