Error NG0900 An error occurred while trying to compare. Only arrays and iterable objects allowed

Using *ngFor I am able to render the data but it throws this error Error: NG0900: An error occurred while trying to compare '[objectObject]'. Only arrays and iterable objects are allowed This is my service method asyncgetEditions():Promise<Observable<Cigales>>{returnthis.http.get<Ciga...

P粉226667290 2024-02-25 19:15:04 0  1  467

javascript - What is the role of weak set in ES6?

Weak set is not iterable and cannot use for-of, keys(), values(), forEach() to traverse values. So what is its function? Is it just about storing objects?

某草草 2017-05-19 10:43:42 0  1  560

How to find JSON data based on other content in a JSON object when duplicates exist?

I'm currently implementing some data charts on a website, and I have a JSON that contains some data, specifically some ID numbers, some dates, and some data points. Because I have multiple dates under the same ID, I'm looking for a way to do essentially "find a JSON object with this ID and mont...

P粉713846879 2024-04-04 10:57:45 0  1  558

Why does the Slice pipeline in Angular cause my code to crash?

Okay, I have this component and I'm iterating over the data. Everything is great without the slice tube. Things work differently when I add a slicing pipeline to limit the output. Angular sends this error on Objectisoftype'unknown'.ngtsc(2571) which is the data store on the API. It returns as an obj...

P粉745412116 2024-03-21 23:18:56 0  1  407

CSS selector finds subset of entities based on class filter

I have a table that contains a set of rows represented, and within that set of tables, some rows have a "clickable" category. What I'm trying to do is apply a style to every odd row that has a "clickable" category. I've tried various selectors, but it only seems to apply the styl...

P粉293550575 2023-09-06 23:21:53 0  1  594

React error: Item is not iterable when adding to state

I'm currently trying to use the spread operator to push items into an array in React, but I'm getting the following error. The error occurs in the PhotoUploader component within PlacesForm.jsx. I've included the code into the component below. PlacesForm.jsx: importaxiosfrom'axios'importReact,{useEff...

P粉709644700 2024-03-27 17:49:53 0  1  486

Vue checkbox returns Null when unchecked

I'm writing a Vue application using Vuetify. In this application, I use v-for to iterate over an array of objects to build a list of cards. Inside each card is a checkbox mapped to a calculated getter/setter that updates the value in my Vuex store. When the checkbox is selected I log out the value a...

P粉637866931 2024-03-26 22:07:01 0  1  437

Why is the write method in the http.ServerResponse object in node.js synchronous?

{code...} The last two lines are 1 and 5! The book says that the http.ServerResponse object implements a stream.Writable (writable stream). However, writable streams are generally asynchronous (such as fs write stream, zlib stream, stdin of subprocess), which is perfect for the event-driven service ...

给我你的怀抱 2017-05-31 10:38:35 0  3  681

MySQL self-join missing data

I want to perform a self-join on a table to present the values ​​column-wise. For each object, there are multiple properties (up to a known limit), but not all properties for all objects are stored. I have tried various joins but there are always missing rows and I want null values. Starting table: ...

P粉464208937 2024-03-31 10:07:32 0  1  388

"Using the v-for directive for array element and attribute destructuring"

When using an array of objects, is it possible in a v-for loop to simultaneously assign the current object to a variable and destructure its properties? Like this: <divv-for="(person={name,age},index)inpersons">Eventually I want to be able to use both the entire person object and its...

P粉420958692 2023-11-05 17:37:54 0  1  653

Access object properties using computed property names

I'm trying to access an object's properties using dynamic names. Is this possible? constsomething={bar:"Foobar!"};constfoo='bar';something.foo;//The idea is to access something.bar and get "Foobar!"

P粉578680675 2023-08-20 15:32:14 0  2  498

Restore table structure from frm and ibd files

I'm trying to restore the database in the PMA but can only access the frm and ibd files - not the ib_log file which I understand you need. I know that I may not be able to recover the database data, but is it possible to recover the structure of the table from the frm file?

P粉637866931 2023-10-19 10:01:37 0  2  748

Is it possible for the code to skip an iteration in web scraping? IndexError: popup index out of range

So I have a code that removes the name + price of a mineral from 14 pages (so far) and saves it to a .txt file. I first tried using only Page1, then I wanted to add more pages to get more data. But then the code grabs something it shouldn't - random names/strings. I didn't expect it to grab that one...

P粉846294303 2024-02-21 19:40:15 0  2  426

Does using undefined as a property key guarantee that the result will be undefined?

In the case of retrieving object properties via a variable, ie: myObject[someField]someField (which is a string) has the potential to be undefined (possibly the result of an uninitialized string value). My experiments show that for every type of object I can think of, the result is undefined, i.e.: ...

P粉504920992 2024-01-16 23:42:26 0  1  515

Laravel 5 opens the page and reports an error

I have two questions: 1. Local php artisan serve works. 2. I don’t know why after moving the server, it will create or read files in the / directory, so there is no permission, and an error is reported. 3. It is a permission directory, and I have also 777ed the directory, but here It should not be a...

过去多啦不再A梦 2017-05-16 16:48:24 0  4  570

Are parameters passed in JavaScript by value or by reference?

Primitive types (numbers, strings, etc.) are passed by value, but objects are unknown since they can either be passed by value (in which case we think the variable holding the object is actually a reference to the object), It is also possible to pass by reference (in which case we consider the varia...

P粉394812277 2023-08-21 15:57:16 0  1  589

Can PHPUnit use assert equals to strictly compare two arrays containing objects?

I have two arrays of objects. I want to test if these two arrays are equal, but using a strict comparison such as 'false'!==0. Is it possible to achieve this in phpunit without requiring custom comparators or other methods?

P粉162773626 2024-04-05 13:35:37 0  1  1622

javascript - There are some uncertain factors. Will everyone choose to save it as a variable? ~

For example, if you need to use an attribute of an object returned by an external method (assuming that this attribute is not of Object type and may be updated and cannot be saved as a variable...), will you save the key of this attribute in case it changes? Once the attribute is named, just change ...

世界只因有你 2017-05-19 10:34:18 0  2  512

vue vee-validate captures the problem of date picker selection

The v-model binding on my datepicker field is not working properly. When you make a selection it will update live on the screen but it will not store the value in the formValues ​​reactive object. Since vee-validate does not support date picker fields, how do I force it to update to the same react c...

P粉936568533 2024-04-06 11:38:56 0  1  698

python2.7 - How to create non-fixed classes using Python?

I'm new to python and can't find what I want to search for. For example, read data from a json configuration file, then create class objects based on the data, and then call the methods of these objects. The data of this json configuration file can be set freely. There may be a set of data correspon...

世界只因有你 2017-06-12 09:22:44 0  4  854