Dynamic data update in JavaScript Chart control

18 Nov 20181 minute to read

The JavaScript Chart control provides methods to dynamically modify data without requiring a full chart refresh. This enables real-time data visualization, interactive features, and responsive user experiences. Common scenarios include adding sensor readings, removing outdated data points, replacing entire datasets, and enabling click-based data manipulation.

Adding a new data point

Use the addPoint method to dynamically append a new data point to a series. This is useful for real-time data streams, user interactions, or incremental data loading. The method accepts the following parameters:

  • Data point (required): The new data object to append to the series (must match the datasource structure)
  • Animation duration (optional): Duration in milliseconds for the entry animation

Removing an existing data point

Use the removePoint method to dynamically delete a data point from a series by its index. This is useful for filtering data, removing outliers, or responding to user actions. The method accepts the following parameters:

  • Point index (required): The zero-based index of the data point to remove
  • Animation duration (optional): Duration in milliseconds for the exit animation

Replacing entire data points

Use the setData method to replace all data points in a series with a new dataset. This is useful for category switching, time range changes, or complete data refreshes. The method accepts the following parameters:

  • New data source (required): The complete new dataset array to display
  • Animation duration (optional): Duration in milliseconds for the transition animation

Click to add or remove a data point

Enable users to add or remove data points by clicking on the chart. Listen to the chartMouseClick event to capture click coordinates and point information. When a user clicks within the chart area, extract the x and y axis values from the event arguments. If the location is empty, use addPoint to add a new data point at those coordinates. If a user clicks on an existing data point, identify its index and use removePoint to delete it. This creates an intuitive interface for data exploration and editing.