Conditionally apply filters with ng-repeat

Question

I have an object that contains a mixture of numbers and text for values. I'd like to apply the numbers filter to the object's value when it's a number (obviously). But when it isn't a number, I'd be okay with it just spitting out the string. As is, applying | number to the value formats the numbers, but leaves the string values empty (afterall, they aren't numbers).

I'm guessing it'll have to be a custom filter (which I have yet had a need to make). Is there a way to do it solely within the HTML when doing the ng-repeat?

<table>
      <tr ng-repeat="(metric, metricData) in data">
        <td>{{metric}}</td>
        <td>{{metricData | number}}</td>
      </tr>
</table>

$scope.data = { name:"this is the name", 
                score:48
                outcome:"as expected",
                attendance:820,
                total:212.34
              };

Solution 1

Here is the requested alternate version of the answer from @callmekatootie using ng-if (v1.1.5):

<table>
    <tr ng-repeat="(metric, metricData) in data">
        <td>{{metric}}</td>
        <td ng-if="isNumber(metricData)">{{metricData | number}}</td>
        <td ng-if="!isNumber(metricData)">{{metricData}}</td>
    </tr>
</table>

This has the advantage of only running the filter on the elements which are numeric. This is probably of little benefit in this case but may be useful in other more complex filter situations. To answer your other question about the built-in angular.isNumber, @callmekatootie does use that in the scope function isNumber, which is only a wrapper for using the built-in in the view.

Here is a fiddle

Solution 2

I know this is old, but I think the best solution is to move the logic to a filter.

app.filter("metricDataFilter", function($filter) {
    return function(value) {
      if(angular.isNumber(value)) {
          return $filter("number", value);  
      }

      return value;
    }  
}

That way the HTML is more concise, and angular won't have to redraw dom elements

<table>
    <tr ng-repeat="(metric, metricData) in data">
        <td>{{metric}}</td>
        <td>{{metricData | metricDataFilter}}</td>
    </tr>
</table>

Solution 3

You could try it this way - In your controller, you can have a function which identifies if the provided value is a string or a number:

$scope.isNumber = function (value) {
    return angular.isNumber(value);
};

Next, in your view you could have the following:

<table>
    <tr ng-repeat="(metric, metricData) in data">
        <td>{{metric}}</td>
        <td ng-show="isNumber(metricData)">{{metricData | number}}</td>
        <td ng-hide="isNumber(metricData)">{{metricData}}</td>
    </tr>
</table>

Thus, when the metricData is a number, it is filtered and when it is a string, it is output as it is.

Comments

[callmekatootie]

Just so you know, customer filter is not a bad way of doing it...

[EnigmaRM]

I imagine it is not. I just haven't learned how to do it yet. Maybe it's time I learn. ha.

[Dan]

+1 A variation could use ng-if (v. 1.1.5+) so the data set isn't filtered at all in the off case (this may save time with large data sets / complex filters).

[EnigmaRM]

I like this solution. Doesn't angular have a built-in isNumber directive? angular.isNumber? I tried using that for something else, but couldn't get it to work in the HTML.

[EnigmaRM]

@sh0ber what is the proper syntax for using ng-if? I just upgraded my angular version to 1.1.5. But I don't find any documentation about the use of that directive. Just been told "use it like ng-switch"... Would you be willing to submit a solution using nf-if? Thanks.

[callmekatootie]

I think also OP wanted to know if in built function angular.isNumber() can be used directly inside the HTML code, which I do not think is possible. Correct?

[Dan]

@callmekatootie I think so, expressions seem to only support variables on a scope.

[Jason]

I think show/hide on a <td> could cause issues...better use ng-if / ui-if