{"id":32,"date":"2026-10-04T09:20:00","date_gmt":"2026-10-04T09:20:00","guid":{"rendered":"https:\/\/excelgames.cc\/blog\/?p=32"},"modified":"2026-10-04T16:25:43","modified_gmt":"2026-10-04T16:25:43","slug":"data-validation-for-clean-player-input","status":"publish","type":"post","link":"https:\/\/excelgames.cc\/blog\/data-validation-for-clean-player-input\/","title":{"rendered":"Data Validation for Clean Player Input"},"content":{"rendered":"<p><strong>TL;DR:<\/strong> Restrict moves to legal values before formulas execute\u2014dropdowns, ranges, and custom formulas stop illegal game states early. Same pattern protects shared sheets linked from <a href=\"https:\/\/excelgames.cc\/\">Excel Games<\/a> tutorials.<\/p>\n<h2>Dropdown moves<\/h2>\n<p>List source =NamedRange LegalMoves that formulas refresh each turn. Reject blank with \u201cStop\u201d style error.<\/p>\n<h2>Numeric bounds<\/h2>\n<p>Whole number 1\u201320 for stat allocation; sum check elsewhere ensures budget 20 points.<\/p>\n<h2>Custom formula validation<\/h2>\n<p>=AND(A1&gt;=1,A1&lt;=10,ISNUMBER(A1)) for level pick; cross-cell =MOD(A1,2)=0 if even picks only.<\/p>\n<h2>Input messages<\/h2>\n<p>Show hint \u201cPick adjacent cell notation like B3\u201d on select\u2014reduces support.<\/p>\n<h2>Circular reference prevention<\/h2>\n<p>Validation cannot fix circular logic\u2014pair with careful formula layering; validation stops dumb input not formula bugs.<\/p>\n<h2>Unlock validated cells only<\/h2>\n<p>Sheet protect + Allow Edit Ranges for move cell only.<\/p>\n<h2>Copy\/paste bypass<\/h2>\n<p>Users paste invalid values\u2014Worksheet_Change macro revert or audit log.<\/p>\n<h2>Browser parity<\/h2>\n<p>HTML select elements emulate validation in browser ports\u2014keep option list synced with sheet version.<\/p>\n<p>Dirty player input destroys spreadsheet games faster than flawed random formulas. A typo in a move cell cascades into #VALUE errors, phantom collisions, or silent score inflation. Data validation is the gatekeeper: restrict cells to lists, numeric ranges, dates, or custom formulas that reject impossible states before recalc runs. Polished experiences at <a href=\"https:\/\/excelgames.cc\/\">Excel Games<\/a> rarely let you type arbitrary text into action cells\u2014they guide you through dropdowns or buttons precisely to avoid this failure class.<\/p>\n<p>List validation suits discrete moves\u2014compass directions, chess algebraic squares if enumerated, item IDs from a loot table. Set Allow to List and point at a range or inline comma list. Turn on in-cell dropdown so mobile players tap instead of type. Error alerts should explain what is legal, not merely say invalid entry\u2014copy matters for first-time players in training sessions.<\/p>\n<p>Whole-number validation with min and max bounds caps stats during character creation\u2014no 9999 HP slips through. Decimal validation helps percentage sliders. Custom formula validation expresses complex rules: =AND(LEN(B2)=2, ISNUMBER(MATCH(B2,LegalMoves,0))) enforces coordinate pairs present in a legal move table.<\/p>\n<p>Input messages versus error alerts serve different UX beats. Input messages teach before edit begins; error alerts fire after a bad commit. Use both sparingly\u2014modal spam annoys veterans. For classroom games, keep messages short enough to read on a projected screen from the back row.<\/p>\n<p>Circular dependency risks appear when validation formulas reference cells that themselves depend on the validated cell. Structure validation to read from lookup tables and current board state, not from downstream outcomes still calculating. If Excel warns circular references on open, fix validation logic before distributing to thirty students.<\/p>\n<p>Protecting validated cells pairs with sheet protection: unlock only input cells, lock formula regions, apply protection with password optional for casual play. Players can still paste over validation if you leave formats unlocked\u2014consider blocking paste via VBA in macro builds or instruct facilitators to watch for bulk paste sabotage in competitive rooms.<\/p>\n<p>Testing validation is boring and essential. Attempt every illegal move you can imagine\u2014empty submit, lowercase when uppercase required, out-of-range numbers, copy-paste from web pages with trailing spaces. Unicode spaces break exact matches often.<\/p>\n<p>When you author your next game, sketch allowed inputs on paper first, then mirror each rule in validation before writing game logic. Cross-check friendly dropdown flows against quiz and puzzle titles on Excel Games\u2014players should feel guided, not policed, while the sheet stays structurally safe from one mistyped letter breaking the evening.<\/p>\n<p>Dropdown arrow size on Mac Excel can frustrate touchpad users\u2014widen input columns and increase row height so dropdown affordance is obvious during timed rounds.<\/p>\n<p>Batch paste from chat into validated cells often introduces smart quotes or trailing spaces\u2014use CLEAN and TRIM in a staging column before scores commit to leaderboard formulas, or reject paste outright with worksheet protection.<\/p>\n<p>Facilitator override cell protected by password allows legal exception moves in teaching moments without unlocking entire sheet\u2014document override usage in session notes for auditability in training simulations.<\/p>\n<p>Input masks for coordinate entry like A1 notation can use LEN and ISNUMBER(MID()) stacks\u2014heavy but macro-free. Simpler pattern: separate row and column dropdowns validated against board dimensions; beginners understand numbers better than chess notation anyway in corporate training contexts.<\/p>\n<p>Clipboard hygiene workshops matter when games run in browser and desktop copies simultaneously\u2014paste from web tables introduces non-breaking spaces that fail exact match validation silently. Provide Paste Special Values button on facilitator ribbon or written instruction to paste into Notepad first when imports fail mysteriously.<\/p>\n<h2>Paste attack awareness<\/h2>\n<p>Warn players not paste from web into move cell\u2014malicious CSV injection rare but teach paste values only habit.<\/p>\n<p>Validate list rejects formulas starting with = in move cell.<\/p>\n<p>Before sharing a workbook built around data validation for clean player input, save a copy with play-sheet formulas replaced by values so recipients cannot break logic accidentally. For play-only sessions, link classmates to Excel Games instead of emailing macro files IT will block.<\/p>\n<p>Version tags in the Instructions tab\u2014Excel build, date, author\u2014save support time when someone says the sheet worked yesterday. Browser games on the official site always serve the current build after refresh.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Dropdown moves and error alerts that stop illegal choices before they break logic.<\/p>\n","protected":false},"author":1,"featured_media":8,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-32","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-spreadsheet-tips"],"blocksy_meta":{"styles_descriptor":{"styles":{"desktop":"","tablet":"","mobile":""},"google_fonts":[],"version":8}},"_links":{"self":[{"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/posts\/32","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/comments?post=32"}],"version-history":[{"count":6,"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/posts\/32\/revisions"}],"predecessor-version":[{"id":176,"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/posts\/32\/revisions\/176"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/media\/8"}],"wp:attachment":[{"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/media?parent=32"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/categories?post=32"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/excelgames.cc\/blog\/wp-json\/wp\/v2\/tags?post=32"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}