JavaScriptCore介绍

JavaScriptCore C API

JSBase.h

//检查JavaScript 字符串中的语法错误。bool JSCheckScriptSyntax(JSContextRef ctx, JSStringRef script, JSStringRef sourceURL, int startingLineNumber, JSValueRef *exception);//执行一段js语句JSValueRef JSEvaluateScript(JSContextRef ctx, JSStringRef script, JSObjectRef thisObject, JSStringRef sourceURL, int startingLineNumber, JSValueRef *exception);//执行JavaScript GC  在JavaScript执行期间，一般不需要调用此函数; JavaScript 引擎将根据需要进行垃圾回收，在释放对上下文组的最后一个引用时，将自动销毁在上下文组中创建的JavaScript值。void JSGarbageCollect(JSContextRef ctx);

JSContextRef.h

//获取全局的 globalObject 对象，该对象将全局的 JavaScript 设置为跟对象，因此我们可以将我们自己的对象定义为 JavaScript 执行环境。JSObjectRef JSContextGetGlobalObject(JSContextRef ctx);// contextGroup 对象提供了虚拟机的功能 简单类比 JSVirtualMachine 但是需要自己管理内存。JSContextGroupRef JSContextGetGroup(JSContextRef ctx);JSContextGroupRef JSContextGroupCreate(void);void JSContextGroupRelease(JSContextGroupRef group);JSContextGroupRef JSContextGroupRetain(JSContextGroupRef group);//globalContext对象是提供执行 js 的环境 简单类比 JSContextJSGlobalContextRef JSGlobalContextCreate(JSClassRef globalObjectClass);//creteJSGlobalContextRef JSGlobalContextCreateInGroup(JSContextGroupRef group, JSClassRef globalObjectClass);//CreateInGroupvoid JSGlobalContextRelease(JSGlobalContextRef ctx);//relaseJSGlobalContextRef JSGlobalContextRetain(JSGlobalContextRef ctx);//retain

JSObjectRef.h

Functions

// 创建 JavaScript 类 JSClassCreate JSClassRelease JSClassRetainJSClassRef JSClassCreate(const JSClassDefinition *definition);JSObjectMake //创建 JavaScript 对象JSObjectMakeArray //创建数组JSObjectMakeConstructorJSObjectMakeDate 、JSObjectMakeErrorJSObjectMakeFunctionJSObjectMakeRegExp//JavaScript 对象作为构造函数来调用JSObjectRef JSObjectCallAsConstructor(JSContextRef ctx, JSObjectRef object, size_t argumentCount, const JSValueRef arguments[], JSValueRef *exception);//JavaScript 对象作为方法来调用JSValueRef JSObjectCallAsFunction(JSContextRef ctx, JSObjectRef object, JSObjectRef thisObject, size_t argumentCount, const JSValueRef arguments[], JSValueRef *exception);JSObjectCopyPropertyNames //获取对象的所有可枚举属性JSObjectDeleteProperty //从对象中删除属性//对 JS 对象的 Private、Property、Prototype 操作JSObjectGetPrivate JSObjectSetPrivateJSObjectGetProperty JSObjectSetPropertyJSObjectGetPrototype JSObjectSetPrototypeJSObjectGetPropertyAtIndex JSObjectSetPropertyAtIndex//对 JS 对象的属性名的操作JSPropertyNameArrayRetainJSPropertyNameArrayReleaseJSPropertyNameArrayGetNameAtIndexJSPropertyNameArrayGetCountJSPropertyNameAccumulatorAddName//JS对象条件判断JSObjectHasProperty //是否有属性JSObjectIsFunction // 是否是一个方法JSObjectIsConstructor // 是否是构造函数

callBacks

Type Alias JSObjectCallAsConstructorCallback //当该对象被座位构造函数调用是响应callbacktypedef JSObjectRef (*JSObjectCallAsConstructorCallback)(JSContextRef ctx, JSObjectRef constructor, size_t argumentCount, const JSValueRef arguments[], JSValueRef *exception);JSObjectCallAsFunctionCallbacktypedef JSValueRef (*JSObjectCallAsFunctionCallback)(JSContextRef ctx, JSObjectRef function, JSObjectRef thisObject, size_t argumentCount, const JSValueRef arguments[], JSValueRef *exception);

JSValueRef.h

//获取JavaScript值类型JSValueGetType//OC基础数据创建JS的值JSValueCreateJSONStringJSValueMakeBooleanJSValueMakeFromJSONStringJSValueMakeNullJSValueMakeNumberJSValueMakeStringJSValueMakeUndefined//JS值转变为OC基础数据JSValueToBooleanJSValueToNumberJSValueToObjectJSValueToStringCopy//存储JSValueJSValueProtectJSValueUnprotect//比较判断JavaScript值类型JSValueIsBooleanJSValueIsNullJSValueIsNumberJSValueIsObjectJSValueIsObjectOfClassJSValueIsStrictEqualJSValueIsStringJSValueIsUndefinedJSValueIsEqualJSValueIsInstanceOfConstructor

JSStringRef.h

JSStringCreateWithCharacters JSStringCreateWithUTF8CStringJSStringGetCharactersPtrJSStringGetLengthJSStringGetMaximumUTF8CStringSizeJSStringGetUTF8CStringJSStringIsEqualJSStringIsEqualToUTF8CStringJSStringReleaseJSStringRetain

JSStringRefCF.h

CFStringRef JSStringCopyCFString(CFAllocatorRef alloc, JSStringRef string);JSStringRef JSStringCreateWithCFString(CFStringRef string);

测试Demo

#import "ViewController.h"#import <JavaScriptCore/JavaScriptCore.h>JSValueRef ObjectGetPropertyCallback(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName, JSValueRef *exception){     NSLog(@"ObjectGetPropertyCallback");    return nil;};JSValueRef ObjectCallAsFunctionCallback(JSContextRef ctx, JSObjectRef function, JSObjectRef thisObject, size_t argumentCount, const JSValueRef arguments[], JSValueRef* exception) {     NSLog(@"ObjectCallAsFunctionCallback");    return JSValueMakeUndefined(ctx);}void ObjectConstructorFinalize(JSObjectRef object) {   NSLog(@"ObjectConstructorFinalize");}bool ObjectConstructorHasInstance(JSContextRef ctx, JSObjectRef constructor, JSValueRef possibleInstance, JSValueRef* exception) {    NSLog(@"ObjectConstructorHasInstance");    return nil;}JSObjectRef ObjectCallAsConstructor(JSContextRef ctx, JSObjectRef constructor, size_t argc, const JSValueRef argv[], JSValueRef* exception) {     NSLog(@"ObjectCallAsConstructor");    return nil;}@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];    JSContextGroupRef contextGroup = JSContextGroupCreate();    JSGlobalContextRef globalContext = JSGlobalContextCreateInGroup(contextGroup, nil);    JSObjectRef globalObject = JSContextGetGlobalObject(globalContext);         JSClassDefinition constructorClassDef = kJSClassDefinitionEmpty;    constructorClassDef.getProperty = ObjectGetPropertyCallback;    constructorClassDef.callAsFunction = ObjectCallAsFunctionCallback;    constructorClassDef.callAsConstructor = ObjectCallAsConstructor;    constructorClassDef.hasInstance = ObjectConstructorHasInstance;    constructorClassDef.finalize = ObjectConstructorFinalize;        JSClassRef loaderClass = JSClassCreate(&constructorClassDef);        JSObjectRef globalObject = JSContextGetGlobalObject(globalContext);        JSStringRef logFunctionName = JSStringCreateWithUTF8CString("log");    JSObjectRef functionObject = JSObjectMakeFunctionWithCallback(globalContext, logFunctionName, &ObjectCallAsFunctionCallback);        JSObjectSetProperty(globalContext, globalObject, logFunctionName, functionObject, kJSPropertyAttributeNone, nil);        JSStringRef logCallStatement = JSStringCreateWithUTF8CString("log()");    JSEvaluateScript(globalContext, logCallStatement, nil, nil, 1,nil);            JSObjectRef loader = JSObjectMake(globalContext, loaderClass, (__bridge void *)(self.view));    JSStringRef myclass = JSStringCreateWithUTF8CString("myclass");    JSObjectSetProperty(globalContext, globalObject, myclass, loader, kJSPropertyAttributeNone, nil);        JSStringRef callMyclass = JSStringCreateWithUTF8CString("myclass.start()");    JSEvaluateScript(globalContext, callMyclass, nil, nil, 1,nil);    /* memory management code to prevent memory leaks */        JSGlobalContextRelease(globalContext);    JSContextGroupRelease(contextGroup);    JSStringRelease(logFunctionName);    JSStringRelease(logCallStatement);}

contextGroup 是JS执行的虚拟机，后续所有的一切基于它来进行globalContext 是JavaScript的执行环境，第一个参数数虚拟机，第二个参数是nil，是使用默认的类来作为跟对象globalObject 获取全局的 globalObject 对象constructorClassDef 定义一个 JavaScript 类，同时设置该类的特殊事件的callback 如getProperty、callAsFunctionloaderClass 创建一个 JavaScript 类loader  通过 JavaScript 类 创建一个 JavaScript 对象JSObjectSetProperty  给全局的 globalObject 对象设置关联信息 @“log”JSEvaluateScript 执行log方法JSObjectSetProperty  给全局的 globalObject 对象设置class JSEvaluateScript 调用 class 的 方法