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plurals

POCanvas: adding canvas.width does not work inside "setInterval"
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copied!<p>Here is my code:</p> <pre><code>var text = "3141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067982148086513282306647093844609550582231725359408128481117450284102701938521105559644622948954930381964428810975665933446128475648233786783165271201909145648566923460348610454326648213393607260249141273724587006606315588174881520920962829254091715364367892590360011330530548820466521384146951941511609433057270365759591953092186117381932611793105118548074462379962749567351885752724891227938183011949129833673362440656643086021394946395224737190702179860943702770539217176293176752384674818467669405132000568127145263560827785771342757789609173637178721468440901224953430146549585371050792279689258923542019956112129021960864034418159813629774771309960518707211349999998372978049951059731732816096318595024459455346908302642522308253344685035261931188171010003137838752886587533208381420617177669147303598253490428755468731159562863882353787593751957781857780532171226806613001927876611195909216420198938095257201065485863278865936153381827968230301952035301852968995773622599413891249721775283479131515574857242454150695950829533116861727855889075098381754637464939319255060400927701671139009848824012858361603563707660104710181942955596198946767837449448255379774726847104047534646208046684259069491293313677028989152104752162056966024058038150193511253382430035587640247496473263914199272604269922796782354781636009341721641219924586315030286182974555706749838505494588586926995690927210797509302955321165344987202755960236480665499119881834797753566369807426542527862551818417574672890977772793800081647060016145249192173217214772350141441973568548161361157352552133475741849468438523323907394143334547762416862518983569485562099219222184272550254256887671790494601653466804988627232791786085784383827967976681454100953883786360950680064225125205117392984896084128488626945604241965285022210661186306744278622039194945047123713786960956364371917287467764657573962413890865832645995813390478027590099465764078951269468398352595709825822620522489407726719478268482601476990902640136394437455305068203496252451749399651431429809190659250937221696461515709858387410597885959772975498930161753928468138268683868942774155991855925245953959431049972524680845987273644695848653836736222626099124608051243884390451244136549762780797715691435997700129616089441694868555848406353422072225828488648158456028506016842739452267467678895252138522549954666727823986456596116354886230577456498035593634568174324112515076069479451096596094025228879710893145669136867228748940560101503308617928680920874760917824938589009714909675985261365549781893129784821682998948722658804857564014270477555132379641451523746234364542858444795265867821051141354735739523113427166102135969536231442952484937187110145765403590279934403742007310578539062198387447808478489683321445713868751943506430218453191048481005370614680674919278191197939952061419663428754440643745123718192179998391015919561814675142691239748940907186494231961567945208095146550225231603881930142093762137855956638937787083039069792077346722182562599661501421503068038447734549202605414665925201497442"; var pi = []; pi = text.split(''); $('document').ready(function () { canvas = document.createElement("canvas"); canvas.width = 15; canvas.height = 100; canvas.style.position = 'absolute'; canvas.style.border = '1px solid'; canvas.border = 'solid 1px'; canvas.style.top = '0px'; canvas.style.left = '0px'; document.body.appendChild(canvas); ctx = canvas.getContext("2d"); draw(); }); function draw() { var i = 0; setInterval(function () { if(i < 50) { ctx.beginPath(); ctx.moveTo(15 * i, 100 - pi[i] * 10); ctx.lineTo(15 * (i + 1), 100 - pi[i + 1] * 10); ctx.stroke(); i++; canvas.width += 15; //console.log(i); }; }, 100) } </code></pre> <p>It totally works if I comment out</p> <pre><code>canvas.width += 15; </code></pre> <p>If I keep it there, <code>canvas.width</code> does increase, but the lines do not show up.</p> <p>Anyone can help? Thanks a lot.</p> <p>The problem solved by putting the width before the line.</p> <h1>But here is my further question: how to draw the lines successively? Right now the older one disappears after the new one.</h1>

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