SharePoint 2019 On Prem - Modern experience - Conditional Formatting not working

Question

Environment: SharePoint 2019 On Premise

Requirement: If a Number column value is equal to 0 then set sp-field-severity--good else set sp-field-severity--warning

Trial: Based on the article at Use column formatting to customize SharePoint have prepared and set the below JSON

{
  "$schema": "https://developer.microsoft.com/json-schemas/sp/v1/column-formatting.schema.json",             
  "elmType": "div",
  "txtContent": "@currentField",
  "attributes": {
    "class": "=if(@currentField <= 0,'sp-field-severity--good', 'sp-field-severity--warning')"
  }
}

However it doesn't work.

I tried to check the DOM it shows as bellow

Note: As per the instructions in MS article I am using https://developer.microsoft.com/json-schemas/sp/v1/column-formatting.schema.json schema as it is SP 2019 On Prem.

What am I missing?

Answer 1

All Excel-style expressions begin with an equal (=) are only available in SharePoint Online (not in SharePoint 2019).

In SharePoint 2019, you have to use the Abstract Syntax Tree (AST) expressions.

So try using below JSON:

{
  "$schema": "https://developer.microsoft.com/json-schemas/sp/v1/column-formatting.schema.json",
  "elmType": "div",
  "txtContent": "@currentField",
  "attributes": {
    "class": {
      "operator": "?",
      "operands": [
        {
          "operator": "<=",
          "operands": [
            "@currentField",
            0
          ]
        },
        "sp-field-severity--good",
        "sp-field-severity--warning"
      ]
    }
  }
}

You can change the inner operator (<=) as per your requirements/conditions. For Example: To set the class attribute if number column value is equal to 0, use:

"class": {
  "operator": "?",
  "operands": [
    {
      "operator": "==",
      "operands": [
        "@currentField",
        0
      ]
    },
    "sp-field-severity--good",
    "sp-field-severity--warning"
  ]
}

Output: