Enable / Disable or Locked Text Boxes

[aamer]

I am trying to write a code on a subform "SalesSubform"
If TextBox "Loc" = Null Then TextBox "Text56" and TextBox "Text86" and TextBox "Text530" are locked or disabled/locked
and If TextBox "Loc" is not null then the TextBoxes "Text56" "Text86" "Text530" are enabled.

how can I write this code, I will put this code in ON CURRENT Properties of "SalesSubform"

[June7]

If you want this to be dynamic per record on continuous or datasheet form, must use Conditional Formatting. Recommend CF even if single view form.

If you use VBA, will likely need code in Current event as well as textbox Loc AfterUpdate.

[aamer]

Can you guide where can I read about this

[June7]

About what - Conditional Formatting?

Search web. Common topic.

Any introductory book on Access should have guidance.

[aamer]

conditional formatting is not the solution
as on the form if loc value is null then it should lock or disable the textboxes "Text56" "Text86" "Text530 so no data input unless a value in loc is entered.

[June7]

Why not?

A CF rule could be an expression. If expression is true then control will be disabled. As soon as value is entered, textbox will enable. If entered Loc value is removed then textbox will disable again.

[Loc] Is Null