[IgxGrid] - How to change filter operator per column programmatically?

[mddifilippo89]

Question

How to change filter operator per column programmatically? eg. Great Than, Starts With

eg.
Contains - is default for string columns.
Equals - is the default for numeric columns

[ddaribo]

Hi @mddifilippo89,

If you’d like to modify the default filter operation for a given filtering operand, that is the first one appearing in the list, you could create a custom filtering operand. Sample code and a demo can be found in our documentation here.

Since your requirement is to essentially perform a reorder of the operations array, here is an example logic:

export class CustomOrderedStringFilteringOperand extends IgxStringFilteringOperand {
  private constructor() {
    super();

    this.moveStartsWithOperand();
  }
  private moveStartsWithOperand() {
   // 'Starts With' is on index 2 by default
    const startsWithOperand = this.operations[2] as IFilteringOperation;
    this.operations.splice(2, 1);
    this.operations.unshift(startsWithOperand);
  }
}

public customOrderedStringFilteringOperand = CustomOrderedStringFilteringOperand.instance();

And an object of this class has to be assigned to the target column’s filters input:

    <igx-column
      field="ProductName"
      header="Product Name"
      [dataType]="'string'"
      [filters]="customOrderedStringFilteringOperand"
    >

Here is a small sample demonstrating this. The custom filtering operand and consequently the custom order will be used for all filter modes – quick, excel style and advanced filtering.