ref

问题 Greetings, I get the difference between pass by value and pass by reference. But pass reference (such as array) by ref and pass array by value is something i can't seem to comprehend. How can you pass a reference by reference? int[] myArray = {1,2,3}; PassByVal(myArray); PassByRef(ref myArray); PassByVal(int[] array) { array = new int[] {7,8,9}; // will not work } PassByRef(ref int[] array) { array = new int[] {10,11,12}; } // will work 回答1: I suggest that you check out this link. It's quite

问题 Greetings, I get the difference between pass by value and pass by reference. But pass reference (such as array) by ref and pass array by value is something i can't seem to comprehend. How can you pass a reference by reference? int[] myArray = {1,2,3}; PassByVal(myArray); PassByRef(ref myArray); PassByVal(int[] array) { array = new int[] {7,8,9}; // will not work } PassByRef(ref int[] array) { array = new int[] {10,11,12}; } // will work 回答1: I suggest that you check out this link. It's quite

问题 I was experimenting with the new C#7 features and I found something strange. Given the following simplified scenario: public struct Command { } public class CommandBuffer { private Command[] commands = new Command[1024]; private int count; public ref Command GetNextCommand() { return ref commands[count++]; } public ref Command GetNextCommand(out int index) { index = count++; return ref commands[index]; } } public class BufferWrapper { private CommandBuffer cb = new CommandBuffer(); // this

问题 I was experimenting with the new C#7 features and I found something strange. Given the following simplified scenario: public struct Command { } public class CommandBuffer { private Command[] commands = new Command[1024]; private int count; public ref Command GetNextCommand() { return ref commands[count++]; } public ref Command GetNextCommand(out int index) { index = count++; return ref commands[index]; } } public class BufferWrapper { private CommandBuffer cb = new CommandBuffer(); // this

问题 I was experimenting with the new C#7 features and I found something strange. Given the following simplified scenario: public struct Command { } public class CommandBuffer { private Command[] commands = new Command[1024]; private int count; public ref Command GetNextCommand() { return ref commands[count++]; } public ref Command GetNextCommand(out int index) { index = count++; return ref commands[index]; } } public class BufferWrapper { private CommandBuffer cb = new CommandBuffer(); // this

问题 I am getting the following error but I am not able to figure out how to fix it someone can help me out. Below is also the link on expo with the complete code. Error on <AppIntroSlider /> which is reported by snack expo Example: Type '{ ref: (ref: any) => any; data: { key: string; title: string; text: string; backgroundColor: string; }[]; renderItem: ({ item }: any) => Element; renderPagination: (activeIndex: number) => Element; scrollX: (scrollXList: any) => any; }' is not assignable to type

问题 I have a big list of items / divs that I need to create programmatically , and I need to implement scrollIntoView buttons for each them. I know how to do it with refs. Whether there is an alternative to refs that might be more performant? 回答1: I believe something like this will work: onScrollClick(ev) { ev.target.scrollIntoView(); } render() { return ( ... <button onClick={this.onScrollClick}>Scroll This Element Into View</button> ) } That assumes you want to scroll the button itself into

问题 I have a method to be called. public void RecordConversation(ref ChannelResource cr) { VoiceResource RecordResource = TServer.GetVoiceResource(); RecordResource.MaximumTime = 6000; RecordResource.MaximumSilence = 6000; RecordResource.TerminationDigits = ""; } To call it in a thread Thread recordThread = new Thread(() => RecordConversation(ref ChanResource)); recordThread.Start(); Of course we get an error. Cannot use ref or out parameter 'ChanResource' inside an anonymous method, lambda

问题 Code: import DrawControl from "react-mapbox-gl-draw"; export default function MapboxGLMap() { let drawControl = null return( <DrawControl ref={DrawControl => {drawControl = DrawControl}}/> ) } I want to load data when the drawControl not null. I check the document that may use callback ref. So, how do I listen the drawControl changes and load data? 回答1: If you want to trigger a re-render after the ref changes, you must use useState instead of useRef . Only that way can you ensure that the

问题 Code: import DrawControl from "react-mapbox-gl-draw"; export default function MapboxGLMap() { let drawControl = null return( <DrawControl ref={DrawControl => {drawControl = DrawControl}}/> ) } I want to load data when the drawControl not null. I check the document that may use callback ref. So, how do I listen the drawControl changes and load data? 回答1: If you want to trigger a re-render after the ref changes, you must use useState instead of useRef . Only that way can you ensure that the