为什么控制台按此顺序提供



我正在制作一个mern电子商务网站,我只想看看useEffect是如何工作的,所以我控制台。登录useEffect的一些部分并加载FilteredResults我看到了--->最初的进入跳过入口1

屏幕截图

但我认为应该是->最初的进入入口1跳过

为什么控制台会给出这个??我是一个发明家,我是一名自学成才的人,所以如果你需要任何额外的信息,请评论。

代码段-->

const loadFilteredResults = (newFilters) => {
console.log("entry")
getFilteredProducts(skip, limit, newFilters).then((data) => {
console.log("entry1")
if (data.error) {
setError(data.error);
} else {
//console.log(data);
setFilteredResults(data.data);
//console.log("size-->");
//console.log(data.size);
setSize(data.size);
setSkip(0);
}
});
};
....
....
useEffect(() => {
init();
console.log("initial");
loadFilteredResults(skip, limit, myFilters.filters);
console.log("skip");
}, []);

//shop.js 的完整代码

import React, { useEffect, useState } from "react";
import Layout from "./Layout";
import Card from "./Card";
import { getCategories, getFilteredProducts } from "./apiCore";
import Checkbox from "./Checkbox";
import RadioBox from "./RadioBox";
import { prices } from "./fixedPrices";
const Shop = () => {
const [myFilters, setMyFilters] = useState({
filters: { category: [], price: [] }
});
const [categories, setCategories] = useState([]);
const [error, setError] = useState(false);
const [limit, setLimit] = useState(3);//prpduct lesss so use 3 but sir used 6
const [skip, setSkip] = useState(0);
const [size, setSize] = useState(0);
const [filteredResults, setFilteredResults] = useState([]);
const init = () => {
getCategories().then((data) => {
if (data.error) {
//console.log("error");
setError(data.error);
} else {
//console.log("set");
//console.log(data);
setCategories(data);
//console.log(data);
}
});
};
const loadFilteredResults = (newFilters) => {
//console.log(newFilters);
console.log("entry")
getFilteredProducts(skip, limit, newFilters).then((data) => {
console.log("entry1")
if (data.error) {
setError(data.error);
} else {
//console.log(data);
setFilteredResults(data.data);
//console.log("size-->");
//console.log(data.size);
setSize(data.size);
setSkip(0);
}
});
};
const loadMore = () => {
console.log("skip"+skip);
console.log("limit"+limit);
let toSkip = skip + limit;
console.log("toSkip"+toSkip);
getFilteredProducts(toSkip, limit, myFilters.filters).then((data) => {
//console.log("filter");
//console.log( myFilters.filters)
if (data.error) {
setError(data.error);
} else {
//console.log(filteredResults);
//console.log(data.data);
setFilteredResults([...filteredResults, ...data.data]);
//console.log("after");
//console.log(...filteredResults);
//console.log(filteredResults);
//console.log(filteredResults);
//console.log([...filteredResults])
//console.log([...filteredResults, ...data.data])
setSize(data.size);
setSkip(toSkip);
}
});
};
const loadMoreButton = () => {
return (
size > 0 &&
size >= limit && (
<button onClick={loadMore} className="btn btn-warning mb-5">
load more
</button>
)
);
};
useEffect(() => {
init();
//console.log(skip);
console.log("initial");
loadFilteredResults(skip, limit, myFilters.filters);
console.log("skip");
}, []);
const handleFilters = (filters, filterBy) => {
//console.log("SHOP", filters, filterBy);
const newFilters = { ...myFilters };
//console.log(newFilters);
newFilters.filters[filterBy] = filters;
//console.log(typeof(filters));
if (filterBy === "price") {
let priceValues = handlePrice(filters);
newFilters.filters[filterBy] = priceValues;
//console.log(priceValues);
}
//console.log(myFilters.filters);
loadFilteredResults(myFilters.filters);
setMyFilters(newFilters);
};
const handlePrice = (value) => {
const data = prices;
let array = [];
//console.log(value);
for (let key in data) {
if (data[key]._id === parseInt(value)) {
array = data[key].array;
}
}
return array;
};
// const x = (filters)=>{
//   console.log("filters:"+filters);
//   handleFilters(filters, "category")
// }
return (
<Layout
title="Shop Page"
description="search and buy books of your choice"
className="container-fluid"
>
<div className="row">
<div className="col-4">
<h4>Filter by categories</h4>
<ul>
{/* below will be show in list show we wrap it in unorder list */}
<Checkbox
categories={categories}
handleFilters={(filters) =>
handleFilters(filters, "category")
}
/>
</ul>
<h4>Filter by price range</h4>
<div>
<RadioBox
prices={prices}
handleFilters={(filters) => handleFilters(filters, "price")}
/>
</div>
</div>
<div className="col-8">
<h2 className="mb-4">Products</h2>
<div className="row">
{filteredResults.map((product, i) => (
<Card key={i} product={product} />
))}
</div>
<hr />
{loadMoreButton()}
</div>
</div>
</Layout>
);
};
export default Shop;

getFilteredProducts必须是Promise。请阅读使用承诺

在JavaScript事件循环当前运行的完成。

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