There is an array with multiple array. My aim is to build a html-table with this data. Therefore the length of each array must be the same.
Now I want to remove empty rows or colomns: If all last elements of each array are empty (=empty string) or the last array has only empty string, they should be removed.
So this
var data = [
[ 'field 1', 'field 2', '' ],
[ 'field 1', 'field 2', '' ],
[ 'field 1', 'field 2', '' ],
[ '', '', '' ]
];
should become:
var dataNew = [
[ 'field 1', 'field 2' ],
[ 'field 1', 'field 2' ],
[ 'field 1', 'field 2' ]
];
This is what I got so far:
data = removeEmpty(data);
function removeEmpty(data) {
// check for empty colomn at the end
var colHasValue = false,
len = data.length;
while (len--) {
if (data[len][data[len].length - 1]) {
unchanged = true;
break;
}
}
if (!colHasValue) {
data = data.map(function (v) {
return v.slice(0, -1);
});
}
// check for empty row at the end
var rowHasValue = false,
lastArray = data[data.length - 1],
len = lastArray.length;
while (len--) {
if (lastArray[len]) {
hasValue = true;
break;
}
}
if (!rowHasValue) {
data.pop();
}
return data;
}
This is working so far. But what should I do if there are two empty rows or colomns at the end?
Example:
var data = [
[ 'field 1', 'field 2', '', '' ],
[ 'field 1', 'field 2', '', '' ],
[ 'field 1', 'field 2', '', '' ],
[ '', '', '', '' ],
[ '', '', '', '' ]
];
should become:
var dataNew = [
[ 'field 1', 'field 2' ],
[ 'field 1', 'field 2' ],
[ 'field 1', 'field 2' ]
];
Update:
In this case nothing should be done to the array, as the last col/row aren't completely empty:
var data = [
[ 'field 1', 'field 2', '', '' ],
[ 'field 1', 'field 2', '', 'content' ],
[ 'field 1', 'field 2', 'content', '' ],
[ '', '', 'content', '' ],
[ '', 'content', '', '' ]
];
You can do it by combining Array.prototype.map()
with Array.prototype.filter()
var dataNew = data.map(function(a){
return a.filter(function(b){
return b.trim().length;
});
}).filter(function(itm){
return itm.length;
});
Edit:
var dataNew = data.filter(function(itm){ return itm.join("").length; }), internalCnt;
for (var i = 0, len = dataNew.length; i < 4; i++) {
for (var j = 0, cnt = 0; j < len; j++){ if(dataNew[j][i] == ""){ cnt++; } }
if(cnt == len) {
internalCnt = 0;
while(internalCnt < len){ dataNew[internalCnt].splice(i,1); internalCnt++; } i--;
}
}
console.log(dataNew);
Here is one way to do it: Using map, we go through each array, then filter out the empty strings, then finally filter out the left over empty arrays.
Working Fiddle for the code below
var data = [
[ 'field 1', 'field 2', '', '' ],
[ 'field 1', 'field 2', '', '' ],
[ 'field 1', 'field 2', '', '' ],
[ '', '', '', '' ],
[ '', '', '', '' ]
];
var newArray = data.map(function(el) {
return el.filter(function(a) {
return a !== '';
});
}).filter(function(el){
return el.length > 0;
});
console.log(newArray);
A small pivot will help with Array#reduceRight()
, for going backwards and a check with Array#some()
if the row is not completely empty and then add the data to the result array.
Apply twice for the right orientation.
function killEmpty(array) { function pivot(array) { var empty = false; return array.reduceRight(function (r, a, i) { empty = empty || a.some(function (b) { return b; }); empty && a.forEach(function (b, j) { r[j] = r[j] || [] r[j][i] = b; }); return r; }, []); } return pivot(pivot(array)); } var data = [['field 1', '', 'field 2', ''], ['field 1', '', 'field 2', ''], ['field 1', '', 'field 2', ''], ['', '', '', '']], data2 = [['field 1', 'field 2', '', ''], ['field 1', 'field 2', '', 'content'], ['field 1', 'field 2', 'content', ''], ['', '', 'content', ''], ['', 'content', '', '']]; document.write('<pre>pre ' + JSON.stringify(data, 0, 4) + '</pre>'); document.write('<pre>post ' + JSON.stringify(killEmpty(data), 0, 4) + '</pre>'); document.write('<hr><pre>pre ' + JSON.stringify(data2, 0, 4) + '</pre>'); document.write('<pre>post ' + JSON.stringify(killEmpty(data2), 0, 4) + '</pre>');
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.