20 AG-Grid Interview Questions and Answers

AG-Grid is a feature-rich datagrid that offers many features for developers, including sorting, filtering, pagination, and groupby. When applying for a position that requires knowledge of AG-Grid, it is important to be prepared to answer questions about this tool. In this article, we will review some common AG-Grid interview questions and provide tips on how to answer them.

AG-Grid Interview Questions and Answers

Here are 20 commonly asked AG-Grid interview questions and answers to prepare you for your interview:

1. What is AG-Grid?

AG-Grid is a JavaScript grid that can be used in web applications. It is a fully-featured grid that offers both data binding and editing capabilities.

2. How do you install and configure the core grid package in Angular?

You can install the AG-Grid package through the Angular CLI. Once you have installed the package, you will need to import the AgGridModule into your Angular module. You can then configure the grid in your component by setting the properties on the ag-grid-angular component.

3. Can you explain how to use an external filter with AG-Grid?

You can use an external filter with AG-Grid by setting the filter property in the column definition to be a function. This function will take in the value of the cell and return true if the value should be included in the filter or false if it should be excluded.

4. What’s the difference between single filters, quick filters, and full text search?

Single filters are the simplest form of filtering, and only allow you to filter on one criterion at a time. Quick filters are more powerful, and allow you to filter on multiple criteria at the same time. Full text search is the most powerful form of filtering, and allows you to search for a specific word or phrase across all of the columns in the grid.

5. What are some common issues that people face when using AG-Grid for the first time?

Some common issues that people face when using AG-Grid for the first time include:

– Not understanding how to properly configure the grid
– Not understanding how to properly bind data to the grid
– Having difficulty understanding how to use the grid’s features
– Having difficulty understanding how to customize the grid

6. What are some things you can do to improve performance if your dataset is very large?

Some things you can do to improve performance with very large datasets include:

– Use the server-side row model
– Use pagination
– Use virtualization
– Use a smaller page size
– Use fewer columns

7. How can you make sure a column uses custom formatting before displaying it on the screen?

You can use the colDef.cellFormatter property to set a function that will format the value of a cell before it is displayed. This function will take the value as an input and return the formatted value as a string.

8. Is it possible to add validation rules to cells inside AG-Grid? If yes, then how?

Yes, it is possible to add validation rules to cells inside AG-Grid. This can be done by using the built-in cell editors and providing a custom validation function. The validation function will be passed the current value of the cell and will need to return either true or false depending on whether the value is valid or not.

9. Is it possible to change a cell’s contents after editing has been enabled for it? How?

Yes, it is possible to change a cell’s contents after editing has been enabled for it. This can be done by using the setValue() method on the cell.

10. Can you explain what cell renderers are?

Cell renderers are used to render the contents of a cell in a grid. They can be used to provide custom rendering for a specific cell, or for all cells in a column. Cell renderers can be used to provide custom formatting, to display images or other data, or to provide a custom editor for a cell.

11. Why does the number of columns displayed on the screen differ from the number specified by the colDefs array?

The number of columns displayed on the screen can differ from the number specified by the colDefs array for a number of reasons. One reason is that the grid may be configured to only display a certain number of columns at a time. Another reason is that some of the columns may be hidden.

12. How do you control which columns appear in the header section vs the footer section?

You can use the pinnedColumnCount property to specify how many columns should be pinned to the left-hand side of the header. The remaining columns will be placed in the header’s footer section.

13. How do I hide or show certain rows based on user input?

You can use the filter API to set up filters that will hide or show certain rows based on user input.

14. Is there any way to check whether the value of one cell affects the value of another cell?

There is no built-in way to do this in AG-Grid, but it is possible to write a custom function to check if the value of one cell affects the value of another cell.

15. What’s the best way to get row data in AG-Grid?

The best way to get row data in AG-Grid is to use the getRowData() function. This function will return an array of objects, each of which represents a row in the grid.

16. How do you define attributes like width, height, minWidth, and maxWidth for different columns in AG-Grid?

You can set these attributes either in the column definition object, or directly on the column header component.

17. How do you enable sorting for a column in AG-Grid?

You can enable sorting for a column in AG-Grid by setting the sortable property to true for that column.

18. Is it possible to merge multiple cells into a single cell? If yes, then how?

Yes, it is possible to merge multiple cells into a single cell using the “group” function. This can be done by selecting the cells that you want to merge, right-clicking, and selecting “group.”

19. In angular, why does the app crash with a “cannot read property ‘length’ of undefined” error message?

This error message usually indicates that the data that you are trying to display in the grid is undefined. This can happen if the data is not being correctly fetched from the server, or if there is an error in the way that the data is being parsed.

20. What is the purpose of the node.parentNode attribute?

The node.parentNode attribute is used to return the parent node of the specified node. This is useful for traversing the DOM tree and for understanding the structure of the XML document.