The problem of dynamically generating a table with N rows and N columns from a one-dimensional array

Someone asked me a question just now. The content of the question is roughly as follows:

Now I need to generate a 7-column table. All the contents of the table are stored in a JavaScript one-dimensional array. How to achieve this?

I tried to write the following code, firstly, to keep it as a souvenir, and secondly, in case I need it in the future, I don’t have to look for it everywhere.

The specific code and corresponding comments are as follows:

var arr=[];  
var col=7;//这里为生成7列的表格  
for (var i=0;i<25;i++){arr[i]=i;}//这里只是举例子，在实践中应该为具体数据  
var lines=Math.ceil(arr.length/col);//很关键的一步，这里为生成表格的行数  
var str="<table><tbody>";//表头  
for (var j=0;j<lines;j++){//遍历表格行  
str+="<tr>";  
for (var k=0;k<col;k++){//遍历表格列  
str+="<td>";  
if(typeof arr[k+j*col]=="undefined"){str+="&nbsp";}  
else{str+=arr[k+j*col];}  
str+="</td>";  
};//表格行结束  
str+="</tr>";  
};  
str+="</tbody></table>";  
   
document.body.innerHTML=str;