iOS下JS与OC互相调用

创建一个WKWebView

//创建一个WKWebView
self.webView = [[WKWebView alloc] initWithFrame:self.view.frame configuration:configuration];

    NSString *urlStr = [[NSBundle mainBundle] pathForResource:@"index.html" ofType:nil];
    NSURL *fileURL = [NSURL fileURLWithPath:urlStr];
    [self.webView loadFileURL:fileURL allowingReadAccessToURL:fileURL];

    self.webView.navigationDelegate = self;
    self.webView.UIDelegate = self;
    [self.view addSubview:self.webView];

JS调用OC的方法

 //配置环境
    WKWebViewConfiguration * configuration = [[WKWebViewConfiguration alloc]init];
    userContentController =[[WKUserContentController alloc]init];
    configuration.userContentController = userContentController;
//注册方法
    [userContentController addScriptMessageHandler:self  name:@"sayhello"];//注册一个name为sayhello的js方法
//移除
-(void)viewWillDisappear:(BOOL)animated{
    [super viewWillDisappear:animated];
//这里需要注意，前面增加过的方法一定要remove掉，不能在dealloc里面做这件事，
//因为有“sayhello”这个时间的存在所以dealloc这个方法并不会走。不信的你可以试一试。
//在这里我没有跳转二级界面用了这中懒人做法，其实正确的做法是写一个代理方法的类
//专一注册才可以
    [userContentController removeScriptMessageHandlerForName:@"sayhello"];
}

#pragma mark - WKScriptMessageHandler
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message{
    NSLog(@"name:%@\\\\n body:%@\\\\n frameInfo:%@\\\\n",message.name,message.body,message.frameInfo);
}

JS调用OC注册的最正统的方法

@interface ViewController ()<WKUIDelegate,WKNavigationDelegate,WKScriptMessageHandler>{
    WKWebView * webView;
    WKUserContentController* userContentController;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    //配置环境
    WKWebViewConfiguration * configuration = [[WKWebViewConfiguration alloc]init];
    userContentController =[[WKUserContentController alloc]init];
    configuration.userContentController = userContentController;
    webView = [[WKWebView alloc]initWithFrame:CGRectMake(0, 0, 100, 100) configuration:configuration];
    //注册方法
    WKDelegateController * delegateController = [[WKDelegateController alloc]init];
    delegateController.delegate = self;
 
    [userContentController addScriptMessageHandler:delegateController  name:@"sayhello"];
 }
- (void)dealloc{
    //这里需要注意，前面增加过的方法一定要remove掉。
    [userContentController removeScriptMessageHandlerForName:@"sayhello"];
}

WKDelegateController代码：

#import <UIKit/UIKit.h>
#import <WebKit/WebKit.h>
@protocol WKDelegate <NSObject>
 
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message;
 
@end
 
@interface WKDelegateController : UIViewController <WKScriptMessageHandler>
 
@property (weak , nonatomic) id<WKDelegate> delegate;
 
@end

#import "WKDelegateController.h"
 
@interface WKDelegateController ()
 
@end
 
@implementation WKDelegateController
 
- (void)viewDidLoad {
    [super viewDidLoad];
}
 
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message{
    if ([self.delegate respondsToSelector:@selector(userContentController:didReceiveScriptMessage:)]) {
        [self.delegate userContentController:userContentController didReceiveScriptMessage:message];
    }
}
@end

oc调用JS方法

//say()是JS方法名，completionHandler是异步回调block
    [webView evaluateJavaScript:@"say()" completionHandler:^(id _Nullable result, NSError * _Nullable error) {
        NSLog(@"%@",result);
    }];