Skip to content

Latest commit

 

History

History
173 lines (130 loc) · 5.68 KB

README.zh-Hans.md

File metadata and controls

173 lines (130 loc) · 5.68 KB
Raw

这是什么？

一个安全、简单、高效的 Swift/Objective-C hook库，可以动态修改某个对象的方法或者一个类所有对象的某个方法。 它支持 Swift 和 Objective-C，与 KVO 具有良好的兼容性。

它基于 Objective-C 运行时和 libffi。

如何使用？

  1. hook某个实例的某个方法，在目标方法执行之前调用 hook 闭包。
class TestObject { // No need to inherit from NSObject.
    // Use `@objc` to make this method accessible from Objective-C
    // Using `dynamic` tells Swift to always refer to Objective-C dynamic dispatch
    @objc dynamic func testMethod() {
        print("Executing `testMethod`")
    }
}

let obj = TestObject()

let token = try hookBefore(object: obj, selector: #selector(TestObject.testMethod)) {
    print("Before executing `testMethod`")
}

obj.testMethod()
token.cancelHook() // cancel the hook
  1. hook某个实例的某个方法，在目标方法执行之后调用 hook 闭包，并且获取方法的参数。
class TestObject {
    @objc dynamic func testMethod(_ parameter: String) {
        print("Executing `testMethod` with parameter: \(parameter)")
    }
}

let obj = TestObject()

let token = try hookAfter(object: obj, selector: #selector(TestObject.testMethod(_:)), closure: { obj, sel, parameter in
    print("After executing `testMethod` with parameter: \(parameter)")
} as @convention(block) ( // Using `@convention(block)` to declares a Swift closure as an Objective-C block
    AnyObject, // `obj` Instance
    Selector, // `testMethod` Selector
    String // first parameter
) -> Void // return value
)

obj.testMethod("ABC")
token.cancelHook() // cancel the hook
  1. hook某个实例的某个方法，用 hook 闭包完全取代目标方法。
class Math {
    @objc dynamic func double(_ number: Int) -> Int {
        let result = number * 2
        print("Executing `double` with \(number), result is \(result)")
        return result
    }
}

let math = Math()

try hookInstead(object: math, selector: #selector(Math.double(_:)), closure: { original, obj, sel, number in
    print("Before executing `double`")
    let originalResult = original(obj, sel, number)
    print("After executing `double`, got result \(originalResult)")
    print("Triple the number!")
    return number * 3
} as @convention(block) (
    (AnyObject, Selector, Int) -> Int,  // original method block
    AnyObject, // `math` Instance
    Selector, // `sum` Selector
    Int // number
) -> Int // return value
)

let number = 3
let result = math.double(number)
print("Double \(number), got \(result)")
  1. hook某个类的所有实例的某个方法，在目标方法执行之前调用 hook 闭包。
class TestObject {
    @objc dynamic func testMethod() {
        print("Executing `testMethod`")
    }
}

let token = try hookBefore(targetClass: TestObject.self, selector: #selector(TestObject.testMethod)) {
    print("Before executing `testMethod`")
}

let obj = TestObject()
obj.testMethod()
token.cancelHook() // cancel the hook
  1. hook某个类的某个类方法或静态方法，在目标方法执行之前调用 hook 闭包。
class TestObject {
    @objc dynamic class func testClassMethod() {
        print("Executing `testClassMethod`")
    }
    @objc dynamic static func testStaticMethod() {
        print("Executing `testStaticMethod`")
    }
}

try hookClassMethodBefore(targetClass: TestObject.self, selector: #selector(TestObject.testClassMethod)) {
    print("Before executing `testClassMethod`")
}
TestObject.testClassMethod()

try hookClassMethodBefore(targetClass: TestObject.self, selector: #selector(TestObject.testStaticMethod)) {
    print("Before executing `testStaticMethod`")
}
TestObject.testStaticMethod()
  1. Hook dealloc 方法
  2. 只 hook 一次
  3. 在 Objective-C 中使用

怎么集成？

使用 cocoapods.

pod 'EasySwiftHook'

或者使用 Swift Package Manager。 3.2.0 版本之后，SPM被支持。确保Xcode的版本大于等于12.5，否则会有编译错误。

性能

和 Aspects 比较 (向 Aspects 致敬).

  • Hook with Before and After mode for all instances, SwiftHook is 13 - 17 times faster than Aspects.
  • Hook with Instead mode for all instances, SwiftHook is 3 - 5 times faster than Aspects.
  • Hook with Before and After mode for specified instances, SwiftHook is 4 - 5 times faster than Aspects.
  • Hook with Instead mode for specified instances, SwiftHook is 2 - 4 times faster than Aspects.

KVO兼容性

自 3.0.0 版本以来，完美兼容KVO。 更多测试用例: Here

We already have great Aspects. Why do I created SwiftHook?

  1. Aspects has some bugs. Click here for test code.
  2. Aspects doesn’t support Swift with instead mode in some cases. Click here for test code.
  3. Aspects’s API is not friendly for Swift.
  4. Aspects doesn’t support Swift object which is not based on NSObject.
  5. Aspects is based on message forward. This performance is not good.
  6. Aspects are no longer maintained. Author said: “STRICTLY DO NOT RECOMMEND TO USE Aspects IN PRODUCTION CODE”
  7. Aspects is not compatible with KVO.

BTW, Respect to Aspects!

Requirements

  • iOS 12.0+, MacOS 10.13+ (Unverified for tvOS, watchOS)
  • Xcode 15.1+
  • Swift 5.0+