当我尝试刷新美国时,为什么我的程序会破裂



当我尝试刷新程序时,我的程序就会破裂。有问题的行是" setMesses(_messages(;"。我试图使美国人资本化,但没有任何改变。

import React, {useState} from 'react';
import Message from './Message';
import * as firebase from "firebase";
function MessContainer() {
    let counter = 0;
    let _messages = [];
    const [messes, setMesses] = useState([{this: null}]);
    firebase.database().ref().child('counter').on('value', function(snapshot){
        counter = snapshot.child("counter").val();
    });
    function load(_counter){
        firebase.database().ref().child('messages/' + _counter).on('value', function(snapshot){        
            let _chet = {}; 
            let _name = snapshot.child("name").val();
            _chet.mess =  _name + ": " + snapshot.child("message").val();
            if(_name === document.getElementById("name").value){
              _chet.status = "right";
            } else {
              _chet.status = "left";
            }
            _messages.push(_chet);
        });
    }

    function loadChet(){
        _messages = [];
        for(let i = 0; i < counter; i++){
            load(i);
        }
        console.log(_messages);
        setMesses(_messages);
        setTimeout(loadChet, 1000); 
    }
    loadChet();
    return (
        <div>{messes.map(_mess => (
            <Message mess={_mess.mess} status={_mess.status} />
        ))}
        </div>
    );
}
export default MessContainer;

发生这种情况的原因是因为您致电 loadChet,并且该调用 setMesses wich wich wich wich wich wich wich wich wich wich wich wich with con rerender并再次致电 loadChet,导致无限循环。

您不应该在功能上调用loadChet,也许使用useEffect并仅调用一次。您何时需要致电loadChet

编辑:

尝试这个

function MessContainer() {
    let counter = 0;
    let _messages = [];
    const [messes, setMesses] = useState([{this: null}]);
    firebase.database().ref().child('counter').on('value', function(snapshot){
        counter = snapshot.child("counter").val();
    });
    function load(_counter){
        firebase.database().ref().child('messages/' + _counter).on('value', function(snapshot){        
            let _chet = {}; 
            let _name = snapshot.child("name").val();
            _chet.mess =  _name + ": " + snapshot.child("message").val();
            if(_name === document.getElementById("name").value){
              _chet.status = "right";
            } else {
              _chet.status = "left";
            }
            _messages.push(_chet);
        });
    }

    function loadChet(){
        _messages = [];
        for(let i = 0; i < counter; i++){
            load(i);
        }
        console.log(_messages);
        setMesses(_messages);
        setTimeout(loadChet, 1000); 
    }
    useEffect(() => {
        loadChet();
    }, [])
    return (
        <div>{messes.map(_mess => (
            <Message mess={_mess.mess} status={_mess.status} />
        ))}
        </div>
    );
}

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