Angular calculate percentage in the html

问题

Angular noob here! I am trying to display a percentage value in my html as follows:

<td> {{ ((myvalue/totalvalue)*100) }}%</td>

It works but sometimes it gives a very long decimal which looks weird. How do i round it off to 2 digits after the decimal? Is there a better approach to this?

回答1:

You can use the toFixed method of Number.

((myValue/totalValue)*100).toFixed(2)

回答2:

You could use a filter, like this one below by jeffjohnson9046

The filter makes the assumption that the input will be in decimal form (i.e. 17% is 0.17).

myApp.filter('percentage', ['$filter', function ($filter) {
  return function (input, decimals) {
    return $filter('number')(input * 100, decimals) + '%';
  };
}]);

Usage:

<tr ng-repeat="i in items">
   <td>{{i.statistic | percentage:2}}</td>
</tr>

回答3:

I often use the built-in 'number' filter for that purpose;

<span>{{myPercentage | number}}</span>

For 2 decimals:

<span>{{myPercentage | number:2}}</span>

For 0 decimal;

<span>{{myPercentage | number:0}}</span>

回答4:

Use ng-bind that would not show curly braces until the expression resolved.

Html

<td ng-bind="roundedPercentage(myValue, totalValue) + '%'"></td>

Controller

$scope.roundedPercentage = function(myValue, totalValue){
   var result = ((myValue/totalValue)*100)
   return Math.round(result, 2);
}

回答5:

You could use angular percent pipe for this.

Simplest solution in a single line within html using angular would be as follows :

<td> {{ myvalue/totalvalue | percent:'2.0-2' }}</td>

if myvalue = 4 & totalvalue = 10, then result will be displayed as

40.00%

for respective html element.

回答6:

Inside your controller.js (angular.js 1.x) or app.component.ts (angular2) calculate a percentage (logic) of a total value with a another value like this.

this.percentage = Math.floor(this.myValue / this.value * 100); 

Then show the percentage in the html.

<p>{{percentage}}%</p>

Simple Math Example: 3/10*100 = 30%. If myValue is 3 and value is 10 your result will be 30. Use Javascript's built in Math.floor() function to round the number and remove the decimal.

来源：https://stackoverflow.com/questions/29989200/angular-calculate-percentage-in-the-html