Essential Books

Verify if is connected to network

suggest change

Swift 

import SystemConfiguration

/// Class helps to code reuse in handling internet network connections.
class NetworkHelper {

    /**
     Verify if the device is connected to internet network.
     - returns:          true if is connected to any internet network, false if is not
     connected to any internet network.
     */
   class func isConnectedToNetwork() -> Bool {
       var zeroAddress = sockaddr_in()
    
       zeroAddress.sin_len = UInt8(sizeofValue(zeroAddress))
       zeroAddress.sin_family = sa_family_t(AF_INET)
    
       let defaultRouteReachability = withUnsafePointer(&zeroAddress) {
           SCNetworkReachabilityCreateWithAddress(nil, UnsafePointer($0))
       }
    
       var flags = SCNetworkReachabilityFlags()
    
       if !SCNetworkReachabilityGetFlags(defaultRouteReachability!, &flags) {
           return false
       }
    
       let isReachable = (flags.rawValue & UInt32(kSCNetworkFlagsReachable)) != 0
       let needsConnection = (flags.rawValue & UInt32(kSCNetworkFlagsConnectionRequired)) != 0
    
      return (isReachable && !needsConnection)
   }
}
if NetworkHelper.isConnectedToNetwork() {
    // Is connected to network
}

Objective-C:

we can check network connectivity within few lines of code as: 

-(BOOL)isConntectedToNetwork
{
    Reachability *networkReachability = [Reachability reachabilityForInternetConnection];
    NetworkStatus networkStatus = [networkReachability currentReachabilityStatus];
    if (networkStatus == NotReachable)
    {
        NSLog(@"There IS NO internet connection");
        return false;
    } else
    {
        NSLog(@"There IS internet connection");
        return true;
    }
}
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Checking for Network Connectivity:
* Checking for Network Connectivity
* Creating a Reachability listener
* Add observer to network changes
* Alert when network becomes unavailable
* Alert when connection becomes a WIFI or cellular network
* Verify if is connected to network
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0 Getting started with iOS
1 UILabel
2 Change Status Bar Color
3 Passing Data between View Controllers
4 Managing the Keyboard
5 UIButton
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8 Checking for Network Connectivity
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131 Convert HTML to NSAttributed string and vice versa
132 Convert NSAttributedString to UIImage
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134 Face Detection Using CoreImageOpenCV
135 MPMediaPickerDelegate
136 Graph Coreplot
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138 FCM Messaging
139 Create Custom Framework
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142 SLComposeViewController
143 AirPrint tutorial
144 UISlider
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146 HealthKit
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166 Simulator
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172 MVP Architecture
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174 Configure Beacons with CoreBluetooth
175 Core Data
176 Extension for rich Push Notification
177 Profiling with Instruments
178 Application rating review request
179 MyLayout
180 UIFont
181 Simulator Builds
182 Simulating Location Using GPX files
183 Custom methods of selection of UITableViewCells
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186 SqlCipher integration
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191 UIFeedbackGenerator
192 UIKit Dynamics with UICollectionView
193 Multicast Delegates
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196 Runtime in Objective-C
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198 CydiaSubstrate tweak
199 Create a video from images
200 Codable
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210 Contributors