Question

考虑一下：

@protocol FooExport <JSExport>
- (void)method1:(NSString *)param1;
- (void)method2:(NSString *)param1 param2:(NSString *)param2;
@end

@interface Foo : NSObject <FooExport>
@end

@implementation Foo
- (void)method1:(NSString *)param1 {
    NSLog(@"method1");
}
- (void)method2:(NSString *)param1 param2:(NSString *)param2 {
    NSLog(@"method2");
}
@end

{
    sContext = [[JSContext alloc] init];
    if (sContext)
    {
        sContext[@"foo"] = [[Foo alloc] init];
        [sContext evaluateScript:@"foo.method1(\"foo\");"]; // method1 is called
        [sContext evaluateScript:@"foo.method2(\"foo\", \"bar\");"]; // method2 is NOT called
    }
}

方法1被调用就好了但是方法2从不被调用。

如果我按如下方式更改method2：

@protocol FooExport <JSExport>
- (void)method1:(NSString *)param1;
- (void)method2:(NSString *)param1;
@end

方法2现在通过[sContext evaluateScript调用：@＆＃34; foo.method2（\＆＃34; foo \＆＃34;，\＆＃34; bar \＆＃34;）;＆＃34; ]。（我必须通过JSContext.currentArguments挖出第二个参数）。

同样，如果我按如下方式更改method2：

@protocol FooExport - （void）method1：（NSString *）param1; - （void）method2; @end

方法2再次通过[sContext evaluateScript调用：@＆＃34; foo.method2（\＆＃34; foo \＆＃34;，\＆＃34; bar \＆＃34;）;＆＃34; ]。（我必须通过JSContext.currentArguments挖出这两个参数）。

这是设计的吗？ JSContext.currentArguments的缺点是我必须处理JSValues而不是已经转换的objective-C类型。

Answer 1

快速浏览JSContext.h揭示了这个gem：

// When a selector that takes one or more arguments is converted to a JavaScript
// property name, by default a property name will be generated by performing the
// following conversion:
//  - All colons are removed from the selector
//  - Any lowercase letter that had followed a colon will be capitalized.
// Under the default conversion a selector "doFoo:withBar:" will be exported as
// "doFooWithBar". The default conversion may be overriden using the JSExportAs
// macro, for example to export a method "doFoo:withBar:" as "doFoo":
//
//    @protocol MyClassJavaScriptMethods <JSExport>
//    JSExportAs(doFoo,
//    - (void)doFoo:(id)foo withBar:(id)bar
//    );
//    @end
//
// Note that the JSExport macro may only be applied to a selector that takes one
// or more argument.
#define JSExportAs(PropertyName, Selector) \
    @optional Selector __JS_EXPORT_AS__##PropertyName:(id)argument; @required Selector

JSExport不能使用多个参数的Objective-C方法吗？

1 个答案: