<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>Document</title> </head> <body> <button onclick="jsFunc()">打开相册按钮</button> <button onclick="jsFunc1()">获取版本号</button> <script> function jsFunc() { alert('返回参数' + common("openCamera","1234567")) }; function jsFunc1() { alert('返回参数' + common("getCode")) }; function common (){ var args = Array.prototype.slice.call(arguments); alert(args); var type = "JSbridge"; var payload = { "type": type, "arguments": args }; return prompt(JSON.stringify(payload)); }; </script> </body> </html>
iOS 代码实现
#include <objc/objc.h> #include <objc/runtime.h> #include <objc/message.h> - (void)webView:(WKWebView *)webView runJavaScriptTextInputPanelWithPrompt:(NSString *)prompt defaultText:(NSString *)defaultText initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(NSString * _Nullable))completionHandler{ NSError *err = nil; NSData *dataFromString = [prompt dataUsingEncoding:NSUTF8StringEncoding]; NSDictionary *payload = [NSJSONSerialization JSONObjectWithData:dataFromString options:NSJSONReadingMutableContainers error:&err]; if (!err) { NSString *type = [payload objectForKey:@"type"]; if (type && [type isEqualToString:@"JSbridge"]) { NSString *returnValue = @""; NSArray *args = [payload objectForKey:@"arguments"]; if (args.count < 1) { completionHandler(returnValue); return; } NSString * functionName = [args firstObject]; NSMutableArray * newArrayArgs = [[NSMutableArray alloc]initWithArray:args]; [newArrayArgs removeObjectAtIndex:0]; SEL sel = newArrayArgs.count < 1 ? NSSelectorFromString(functionName) : NSSelectorFromString([NSString stringWithFormat:@"%@:",functionName]); if ([self respondsToSelector:sel]) { #pragma clang diagnostic push #pragma clang diagnostic ignored "-Warc-performSelector-leaks" returnValue = [self performSelector:sel withObject:newArrayArgs]; #pragma clang diagnostic pop if(![returnValue isKindOfClass:[NSString class]]) { returnValue = @""; } } completionHandler(returnValue); } } } - (NSString *)getAppVersion { NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary]; NSString *app_Version = [infoDictionary objectForKey:@"CFBundleShortVersionString"]; return app_Version; } -(void)openCamera:(NSArray *)argsArray{ if (argsArray.count > 0) { NSString *orderId = argsArray[0]; // 打开相机 } }
这上面注意点
- var type = "JSbridge"; 是web 和 app上确定好的协议
- web 传递的数据是[方法名,参数1,参数2,...]
- 通过方法名字生成方法 sel
- 通过是否有参数来确定使用那种sel,如果有参数那么需要使用带参数的sel,否则使用没有参数的sel
- 通过 performSelector 来执行sel,注意在func没有返回值的时候,那么performSelector返回的就是参数,需要特殊处理一下
- 走过的弯路
Method method = class_getInstanceMethod([self class], sel); const char *types = method_getTypeEncoding(method); NSLog(@"-------- %@",[NSString stringWithUTF8String: types]); // v为 void , i 为 int , f为float // // ? 为 block ( void(^)(void) ) // // 开头带v16 v32表示无返回值,其他带什么表示返回值为什么类型; // // :8 是 SEL标示 // // @28 返回值为 NSString, @16代表参数为 NSString, // // @24 返回值为id, // 通过types来确定返回值是什么 returnValue = ((NSString* (*) (id,SEL))objc_msgSend)(self,sel); ((void (*) (id,SEL))objc_msgSend)(self,sel); returnValue = ((NSString * (*) (id,SEL,id))objc_msgSend)(self,sel,newArrayArgs);
真心的不建议用 objc_msgSend 因为如果要用这个需要更改编译器,这样编译器就不检测类型了,对app 对安全是一个重大的曲线
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作者:SteveKwok