In Power Apps, the With() function is used to create temporary variables (kind of like short-term placeholders) inside a formula. These variables only exist while the formula is being evaluated. This helps make formulas shorter and more readable because you don’t have to repeat calculations or expressions multiple times.

1. Calculations with Shared Logic

Perform complex calculations that share common intermediate logic.

Example: Width, Height, and Depth are named formulas.

With(
    { Area: Width * Height },
    UpdateContext({ Perimeter: 2 * (Width + Height), Volume: Area * Depth })
)

2. Simple Arithmetic

Perform basic calculations and reuse intermediate results.

With(
    { Result: 50 * 10 },
    Result + 50
)

3. Working with Collections

Handle filtered collections easily.

With(
    { MyProducts: Filter(Products, Price > 100) },
    CountRows(MyProducts)
)

4. Nested With()

Sequential or multi-step calculations.

With(
    { Sum: Value(TextInput1.Text) + Value(TextInput2.Text) },
    With(
        { Markup: Sum * 5 },
        Markup / 2
    )
)

5. Using With() in Galleries

Calculate totals or other aggregate values for a gallery.

With(
    { TotalPrice: Sum(Filter(Gallery1.AllItems, Category = "Electronics"), Price) },
    Text(TotalPrice, "$0.00")
)

6. Date and Time Manipulation

Extract date components for filtering or calculations.

With(
    { Today: Now() },
    UpdateContext({ YYYY: Year(Today), MM: Month(Today), DD: Day(Today) })
)

With(
    { StartDate: DateValue("01-01-2022"), EndDate: DateValue("12-31-2022") },
    Filter(Orders, OrderDate >= StartDate && OrderDate <= EndDate)
)

7. Conditional Formatting and Styling

Set visual styles dynamically.

With(
    { Style: If(IsAdmin, Color.Blue, Color.Red) },
    UpdateContext({ HeaderColor: Style, ButtonColor: Style })
)

8. Grouping Operations on a Single Record

Perform multiple operations on a specific record.

With(
    { CurrentProduct: Lookup(Products, ProductID = selectedProductID) },
    Patch(Products, CurrentProduct, { Stock: CurrentProduct.Stock - 1 });
    Notify(CurrentProduct.Stock, NotificationType.Information)
)

9. Navigating Hierarchical Data

Filter related child records in a 1-N relationship.

With(
    { SelectedCategory: Lookup(Categories, CategoryID = selectedCategoryID) },
    UpdateContext({ Subcategories: Filter(Subcategories, ParentID = SelectedCategory.CategoryID) })
)

10. Displaying User Information

Simplify multi-field concatenation.

With(
    { CurrentUser: Lookup(Users, ID = User().Email) },
    Concatenate(
        "Name: ", CurrentUser.FullName, Char(10),
        "Email: ", CurrentUser.Email, Char(10),
        "Phone: ", CurrentUser.Phone
    )
)

11. Converting Duration Strings to Time

Extract hours, minutes, seconds from ISO 8601 duration strings.

With(
    Match("PT2H1M39S", "PT(?:(?<hours>\d+)H)?(?:(?<minutes>\d+)M)?(?:(?<seconds>\d+)S)?"),
    Time(Value(hours), Value(minutes), Value(seconds))
)

12. Creating a New Order with Details

Handle parent-child database operations elegantly.

With(
    { NewOrder: Patch(Orders, Defaults(Orders), { OrderStatus: "New" }) },
    ForAll(
        NewOrderDetails,
        Patch(
            OrderDetails,
            Defaults(OrderDetails),
            { OrderNumber: NewOrder, Quantity: Quantity, ProductID: ProductID }
        )
    )
)

13. Comparing Two Records from Different Sources

Check if two records match.

With(
    { SpecificOrder: Lookup(Orders, OrderID = "Order123") },
    If(
        SpecificOrder.CustomerID = Gallery1.Selected.CustomerID &&
        SpecificOrder.OrderDate = Gallery1.Selected.OrderDate &&
        SpecificOrder.TotalAmount = Gallery1.Selected.TotalAmount,
        true,
        false
    )
)

14. Evaluating Process Status and Sending Emails

Conditional actions based on record status.

With(
    { ProcessRecord: Lookup(Processes, ProcessID = "P123") },
    Switch(
        ProcessRecord.Status,
        "Completed", Office365.SendEmail(ProcessRecord.AssignedTo, "Process Completed", Concatenate("Process ", ProcessRecord.ProcessID, " has been completed"))
    )
)

15. Adding Checked Gallery Items to a Collection

Handle interactive UI selections.

With(
    { CheckedItems: Filter(Gallery1.AllItems, Checkbox1.Value = true) },
    ForAll(
        CheckedItems,
        Collect(CollectedProducts, { ProductID: ProductID, ProductName: ProductName, Price: Price })
    )
)

✅Conclusion