//the array
var TheArray = ['ABCD','EFGH','IJKL'];
//amount of rows
var RowLength = TheArray.length;
//amount of colums
var ColumnLength = TheArray[0].length;
我的代码将对角线分成 4 个循环，以获得所有对角线。它看起来像 2 个 for 循环，其中一个 if 不循环未绑定的值。伪代码看起来有点像这样：
for(loop rows){
var outputarray = [];
for(loop columns){
if(delimit for out of bound){
var temprow = TheArray[something?];
var tempvalue = temprow[something?];
outputarray.push(tempvalue);
}
}
//use values
document.getElementById("theDiv").innerHTML += outputarray.join("")+"<br>";
}
我希望有人能帮助我解决这个问题。
从左上到右下
var theArray = ["ABCD","EFGH","IJKL"];
var length = { "x" : theArray[0].length, "y" : theArray.length };
length.max = Math.max(length.x, length.y);
var temp, k, x, y;
for (k = 0; k <= 2 * (length.max - 1); ++k) {
for (temp = [], y = length.y - 1; (x = k - y), y >= 0; --y) {
x >= 0 && x < length.x && temp.push(theArray[y][x]);
}
temp.length > 0 && (document.body.innerHTML += temp.join('') + '<br>');
}
（也可以看看这个小提琴 https://jsfiddle.net/vu9tnjaL/)
从左下角到右上角
var theArray = ["ABCD","EFGH","IJKL"];
var length = { "x" : theArray[0].length, "y" : theArray.length };
length.max = Math.max(length.x, length.y);
var temp, k, x, y;
for (k = 0; k <= 2 * (length.max - 1); ++k) {
for (temp = [], y = length.y - 1; (x = k + y - length.y), y >= 0; --y) {
x >= 0 && x < length.x && temp.push(theArray[y][x]);
}
temp.length > 0 && (document.body.innerHTML += temp.join('') + '<br>');
}
（也可以看看这个小提琴 https://jsfiddle.net/thkboe4r/)
Combined
由于两者之间只有一行区别，因此您可以轻松地将它们组合在一个函数中：
var theArray = ["ABCD","EFGH","IJKL"];
function diagonal(data, fromBottom) {
var length = { "x" : data[0].length, "y" : data.length };
length.max = Math.max(length.x, length.y);
var temp, k, x, y;
var returnMe = [];
for (k = 0; k <= 2 * (length.max - 1); ++k) {
for (temp = [], y = length.y - 1; y >= 0; --y) {
x = k - (fromBottom ? length.y - y : y);
x >= 0 && x < length.x && temp.push(data[y][x]);
}
temp.length > 0 && returnMe.push(temp.join(''));
}
return returnMe;
}
document.body.innerHTML = diagonal(theArray).join('<br>') +
'<br><br><br>' +
diagonal(theArray, true).join('<br>');
