未捕获的类型错误：无法读取未定义的属性“1”（即使已定义）答案

【问题标题】：Uncaught TypeError: Cannot read property '1' of undefined (even though it is defined)未捕获的类型错误：无法读取未定义的属性“1”（即使已定义）
【发布时间】：2019-05-17 02:07:46
【问题描述】：

所以我们的老师给了我们“生命游戏”项目。我真的为我的项目感到自豪，直到我运行它并收到错误“Uncaught TypeError: Cannot read property '1' of undefined”。对于那些不知道什么是生命游戏的人来说，这是一个“游戏”，你有一个矩阵（这里是一个 8x8 矩阵）和一些规则来定义每个“人”（矩阵中的数字）是否能够生存或不是。 1 表示活着，0 表示死亡。我将附上整个项目以供参考，但这是错误的部分：

function process(matrix) { //creates the next generation

var neighbors = 0,
    position = '',
    nextgen = new Array(8); //the matrix has 8 rows
    for (i = 1; i <= 8; i++) {
        nextgen[i] = new Array(8);
        for (j = 1; j <= 8; j++) {
            neighbors = neighbors(matrix, i, j);

            //Game Rules
                if (neighbors < 2) {nextgen[i][j] = 0;
                } else if (neighbors == 2) {nextgen[i][j] = 1;
                } else if (neighbors <= 3) {nextgen[i][j] = nextgen[i][j];
                } else {nextgen[i][j] = 0;}
        }
    }
    return nextgen;
}

错误出现在if (neighbors < 2) {nextgen[i][j] = 0;}。有人对为什么有任何想法吗？我为nextgen[1]定义了8个数组的时候定义了nextgen[1][1]，对吧？

这是整个项目。名称和所有内容都是德语，所以请记住这一点。

function berechne_nachbarn(matrixb, x, y) { //berechnet die Anzahl der Nachbarn fuer eine Zelle

var zelle = 0,
	 nachbarn = 0,
	 oben = 0,
	 unten = 0,
	 links = 0,
	 rechts = 0;

//loesung fuer die Randzellen
	if (x == 1) {oben = 1} else {oben = x - 1}
	if (y == 1) {links = 1} else {links = y - 1}
	if (x == 8) {unten = 8} else {unten = x + 1}
	if (y == 8) {rechts = 8} else {rechts = y - 1}
	
for (i = oben; i <= unten; i++) {
	for (j = links; j <= rechts; j++) {
		zelle = parseInt (matrixb[i][j]);
		//loesung fuer leere Zellen
		if (isNaN(zelle)) {zelle = 0;}
		nachbarn = nachbarn + zelle;
	}//ende for j
}//ende for i
//die Zelle selbst ist nicht sein eigener Nachbar!
	nachbarn = nachbarn - matrixb[x][y];
	return nachbarn;
}//ende berechne_nachbarn;

function eingabe() {//erstellt Matrix

var spalte = 0,
	 zeile = 0,
	 ort = ''
	 zelle = 0;
	brett = new Array(8); //8 Zeilen
	for (i = 1; i <= 8; i++) {
		brett[i] = new Array(8); //8 Spalten
		for (j = 1; j <= 8; j++) {
			ort = i + 'xx' + j;
				zelle = parseInt(document.formular.elements[ort].value);
				if (isNaN(zelle)) {zelle = 0;}
			brett[i][j] = zelle;
		}//ende for j
	}//ende for i
	return brett;
}//ende eingabe

function verarbeitung(matrix) {//Spielregeln und Verarbeitung

var nachbarn = 0,
	 ort = '',
	nextgen = new Array(8); //neue Matrix fuer neue Generation
	for (i = 1; i <= 8; i++) {
		nextgen[i] = new Array(8);
		for (j = 1; j <= 8; j++) {
			nachbarn = berechne_nachbarn(matrix, i, j);
			
			//Spielregeln
				if (nachbarn < 2) {nextgen[i][j] = 0;
				} else if (nachbarn == 2) {nextgen[i][j] = 1;
				} else if (nachbarn <= 3) {nextgen[i][j] = nextgen[i][j];
				} else {nextgen[i][j] = 0;}
		}//ende for j
	}//ende for i
	return nextgen;
}//ende verarbeitung

function ausgabe(matrix) {//aendert die Werte im Formular

var ort = '';
	for (i = 1; i <= 8; i++) {
		for (j = 1; j <= 8; j++) {
			ort = i + 'xx' + j;
			document.formular.elements[ort].value = matrix[i][j];
		}//ende for j
	}//ende for i
}//ende ausgabe

<body>

<h1> Game Of Life</h1>

<form name = "formular">
	<input name = "1xx1" size = "1">
	<input name = "1xx2" size = "1">
	<input name = "1xx3" size = "1">
	<input name = "1xx4" size = "1">
	<input name = "1xx5" size = "1">
	<input name = "1xx6" size = "1">
	<input name = "1xx7" size = "1">
	<input name = "1xx8" size = "1"> <br>
	<input name = "2xx1" size = "1">
	<input name = "2xx2" size = "1">
	<input name = "2xx3" size = "1">
	<input name = "2xx4" size = "1">
	<input name = "2xx5" size = "1">
	<input name = "2xx6" size = "1">
	<input name = "2xx7" size = "1">
	<input name = "2xx8" size = "1"> <br>
	<input name = "3xx1" size = "1">
	<input name = "3xx2" size = "1">
	<input name = "3xx3" size = "1">
	<input name = "3xx4" size = "1">
	<input name = "3xx5" size = "1">
	<input name = "3xx6" size = "1">
	<input name = "3xx7" size = "1">
	<input name = "3xx8" size = "1"> <br>
	<input name = "4xx1" size = "1">
	<input name = "4xx2" size = "1">
	<input name = "4xx3" size = "1">
	<input name = "4xx4" size = "1">
	<input name = "4xx5" size = "1">
	<input name = "4xx6" size = "1">
	<input name = "4xx7" size = "1">
	<input name = "4xx8" size = "1"> <br>
	<input name = "5xx1" size = "1">
	<input name = "5xx2" size = "1">
	<input name = "5xx3" size = "1">
	<input name = "5xx4" size = "1">
	<input name = "5xx5" size = "1">
	<input name = "5xx6" size = "1">
	<input name = "5xx7" size = "1">
	<input name = "5xx8" size = "1"> <br>
	<input name = "6xx1" size = "1">
	<input name = "6xx2" size = "1">
	<input name = "6xx3" size = "1">
	<input name = "6xx4" size = "1">
	<input name = "6xx5" size = "1">
	<input name = "6xx6" size = "1">
	<input name = "6xx7" size = "1">
	<input name = "6xx8" size = "1"> <br>
	<input name = "7xx1" size = "1">
	<input name = "7xx2" size = "1">
	<input name = "7xx3" size = "1">
	<input name = "7xx4" size = "1">
	<input name = "7xx5" size = "1">
	<input name = "7xx6" size = "1">
	<input name = "7xx7" size = "1">
	<input name = "7xx8" size = "1"> <br>
	<input name = "8xx1" size = "1">
	<input name = "8xx2" size = "1">
	<input name = "8xx3" size = "1">
	<input name = "8xx4" size = "1">
	<input name = "8xx5" size = "1">
	<input name = "8xx6" size = "1">
	<input name = "8xx7" size = "1">
	<input name = "8xx8" size = "1"> <br> <br>
	<br>
	<button type = "button" onClick = "{jetzt = eingabe(); nextgen = verarbeitung(jetzt); ausgabe(nextgen);}"> Next Generation </button>
</form>
</body>

【问题讨论】：

您设法解决了这个问题吗？我的回答对你有帮助吗？
是的，我确实解决了这个问题。有两个问题。一，在countNeighbors，我有maxY = y -1而不是y +1，这导致了奇怪的属性'-1'错误。另一个问题在input。它给了我一个错误，并说我没有定义矩阵。因此，在游戏规则部分之前，我只是将值 0 赋予棋盘的每个单元格，然后查看表单并将值替换为用户输入的值

标签： javascript html arrays properties undefined

【解决方案1】：

我发现了问题。它在berechne_nachbarn 函数中，程序计算游戏板上每个单元格的邻居。在这部分更具体地说：

if (y == 8) {rechts = 8} else {rechts = y - 1}

y - 1 应该是y + 1。

附言。该程序现在可以运行，我为此感到自豪^_^

【讨论】：