Question

I’m using the Google chart on my website and I would like to pass a value to the javascript from my code behind c#. How can I do it?
The value of 0 in the sample below should be a calculated value from C#.

My javascript in the header:

  google.load('visualization', '1', { packages: ['gauge'] });
  google.setOnLoadCallback(drawChart);
  function drawChart() {
      var BudgetData = google.visualization.arrayToDataTable
        ([
            ['Label', 'Value'],
            ['YTD', 0]
        ]);

      var options = {
          width: 350, height: 150,
          max: 100, min: -100
      };
      //Budget
      var chart = new google.visualization.Gauge(document.getElementById('BudgetGauge'));
      chart.draw(BudgetData, options);
  }

And then the graph is shown as:
div id=”BudgetGauge” style=”height: 100px;”>”

Answer 1

You can use the Register array declaration method in C# to register a java script array and then access it from Javascript.

in the page Load

Page.Clientscript.RegisterArrayDeclaration("ArrayName","['Label', 'Value']");
Page.Clientscript.RegisterArrayDeclaration("ArrayName","['YTD', 0]");

then put the array in the arrayToDataTable method like this

var BudgetData = google.visualization.arrayToDataTable(ArrayName);