Change User Agent in UIWebView (iPhone SDK)

Question

I have a business need to be able to customize the UserAgent for an embedded UIWebView. (For instance, I'd like the server to respond differently if, say, a user is using one version of the app versus another.)

Is it possible to customize the UserAgent in the existing iPhone SDK's UIWebView control the way it is, say, for an embedded IE browser in a Windows app?

Answer 1

Very simple in Swift. Just place the following into your App Delegate.

UserDefaults.standard.register(defaults: ["UserAgent" : "Custom Agent"])

If you want to append to the existing agent string then:

let userAgent = UIWebView().stringByEvaluatingJavaScript(from: "navigator.userAgent")! + " Custom Agent"
UserDefaults.standard.register(defaults: ["UserAgent" : userAgent])

Note: You may will need to uninstall and reinstall the App to avoid appending to the existing agent string.

Answer 2

Using @"User_Agent" simply causes a custom header to appear in the GET request.

User_agent: Foobar/1.0\r\n
User-Agent: Mozilla/5.0 (iPhone; U; CPU iPhone OS 3_1_2 like Mac OS X; en-us) AppleWebKit/528.18 (KHTML, like Gecko) Mobile/7D11\r\n

The above is what appears in the dissected HTTP packet, essentially confirming what Sfjava was quoting from that forum. It's interesting to note that "User-Agent" gets turned into "User_agent."

Answer 3

Try this in the AppDelegate.m

+ (void)initialize 

{

    // Set user agent (the only problem is that we can’t modify the User-Agent later in the program)

    // iOS 5.1

    NSDictionary *dictionnary = [[NSDictionary alloc] initWithObjectsAndKeys:@”Mozilla/5.0 (iPad; CPU OS 5_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9B176 Safari/7534.48.3”, @”UserAgent”, nil];


    [[NSUserDefaults standardUserDefaults] registerDefaults:dictionnary];

}

Answer 4

To just add a custom content to the current UserAgent value, do the following:

1 - Get the user agent value from a NEW WEBVIEW

2 - Append the custom content to it

3 - Save the new value in a dictionary with the key UserAgent

4 - Save the dictionary in standardUserDefaults.

See the exemple below:

NSString *userAgentP1 = [[[UIWebView alloc] init] stringByEvaluatingJavaScriptFromString:@"navigator.userAgent"];
NSString *userAgentP2 = @"My_custom_value";
NSString *userAgent = [NSString stringWithFormat:@"%@ %@", userAgentP1, userAgentP2];
NSDictionary *dictionary = [NSDictionary dictionaryWithObjectsAndKeys:userAgent, @"UserAgent", nil];
[[NSUserDefaults standardUserDefaults] registerDefaults:dictionary];

Answer 5

I had this problem too, and tried all methods. I found that only this method works (iOS 5.x): UIWebView iOS5 changing user-agent

The principle is to set the user agent permanently in the user settings. This works; Webview sends the given header. Just two lines of code:

NSDictionary *dictionary = [NSDictionary dictionaryWithObjectsAndKeys:@"Mozilla/Whatever version 913.6.beta", @"UserAgent", nil];
[[NSUserDefaults standardUserDefaults] registerDefaults:dictionary];

Setting User-Agent, or User_Agent in the mutable request, or overriding the setValue in the NSHttpRequest by swizzling, - I tried all that and controlled the results with wireshark, and none of that seems to work, because Webview still uses the user agent value from the user defaults, no matter what you try to set in the NSHttpRequest.

Answer 6

This solution seems to have been seen as a pretty clever way to do it

changing-the-headers-for-uiwebkit-http-requests

It uses Method Swizzling and you can learn more about it on the CocoaDev page

Give it a look !