InputFile in Blazor: Finish the Stream Before Calling It Complete

Select the code and use your copy shortcut. Changes in this preview are temporary.

<!doctype html>
<html lang="en-US"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1"><title>InputFile in Blazor: Finish the Stream Before Calling It Complete</title><style>:root{--bg:#edf1f5;--paper:#fff;--ink:#193449;--accent:#245d86;--tint:#dfeaf2;--line:#c4d0da;--muted:#40586a;--button:#fff}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font:17px/1.55 system-ui,sans-serif}main{max-width:1000px;margin:auto;padding:22px clamp(18px,4vw,42px) 38px}header{border-bottom:2px solid var(--accent);padding-bottom:14px;margin-bottom:18px}h1{font-size:clamp(26px,4vw,36px);line-height:1.15;margin:4px 0 10px}h2{font-size:22px;line-height:1.3;margin:0 0 14px}h3{font-size:19px}p{margin:0 0 14px}.eyebrow{font-size:16px;font-weight:750;color:var(--accent)}.lede{max-width:800px}.panel{background:var(--paper);border:1px solid var(--line);border-radius:9px;padding:20px;margin:18px 0}.workbench{border-top:4px solid var(--accent)}.grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.grid>*{min-width:0}label{display:block;font-size:16px;font-weight:650;margin:12px 0 6px}input,textarea,select{font:inherit;color:var(--ink);background:var(--paper);border:1px solid #7b8893;border-radius:5px;padding:10px;width:100%;min-width:0}textarea{resize:vertical;line-height:1.45}input[type=checkbox],input[type=radio]{width:21px;height:21px;vertical-align:middle;margin-right:9px}button{font:650 16px/1.4 system-ui,sans-serif;padding:11px 15px;min-height:46px;background:var(--accent);border:2px solid var(--accent);color:var(--button);border-radius:5px;cursor:pointer}button:disabled{opacity:.55;cursor:default}.buttons{display:flex;gap:9px;flex-wrap:wrap;margin:14px 0}.buttons>*{flex:1 1 auto}button:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid #c05b00;outline-offset:3px}.result{font:600 17px/1.6 ui-monospace,monospace;white-space:pre-wrap;overflow-wrap:anywhere;background:var(--tint);padding:16px;border-left:4px solid var(--accent);min-height:65px;margin:16px 0}.sample{padding:14px 16px;border-left:3px solid var(--accent);background:var(--tint);margin:12px 0}.muted{color:var(--muted)}pre,code{font:16px/1.6 ui-monospace,monospace;white-space:pre-wrap;overflow-wrap:anywhere}pre{margin:12px 0}table{border-collapse:collapse;width:100%;table-layout:fixed;font-size:16px}th,td{text-align:left;vertical-align:top;padding:10px 8px;border-bottom:1px solid var(--line);overflow-wrap:anywhere}th{background:var(--tint)}svg{max-width:100%;height:auto;display:block}details{margin:20px 0}summary{font-weight:700;cursor:pointer}footer{margin-top:28px;border-top:1px solid var(--line);padding-top:18px;font-size:16px}a{color:var(--accent)}.reading{font-family:Georgia,serif}.codeview{border-radius:0;box-shadow:7px 7px 0 var(--tint)}.token{display:inline-block;padding:8px 12px;margin:4px;border:1px solid var(--line);border-radius:4px;background:var(--paper)}.swatch{min-height:30px}.split{display:grid;grid-template-columns:1.1fr 1fr;gap:22px}ol{padding-left:25px}li{margin:9px 0}@media(max-width:600px){main{padding:16px}.grid,.split{grid-template-columns:1fr}.panel{padding:16px;margin:14px 0}h1{font-size:27px}header{padding-bottom:10px}.buttons{gap:8px}.result{padding:13px}th,td{padding:8px 5px}}</style></head><body><main><header><div class="eyebrow">Original practice fixture · local workbench</div><h1>At 4096 bytes, EOF still matters</h1><p class="lede">The application limit is 4096 bytes. Counts 1024,1024,1024,1024,0 total 4096 bytes and reach EOF: Completed. Replacing the final 0 with 1 totals 4097 bytes: Rejected. A reported Size of 100 cannot raise the limit. Cancellation remains Canceled.</p></header><pre id="result" class="result" role="status" aria-live="polite" aria-atomic="true">4096 bytes + EOF may complete; 4096 bytes alone stays Reading.</pre><label for="chunks">Mock returned counts · 0 means EOF</label><input id="chunks" value="1024,1024,1024,1024,0" ><label for="reported">Client-reported Size</label><input id="reported" value="100" ><div class="buttons"><button type="button" id="evaluate">Evaluate trace</button><button type="button" id="cancel">Cancel current trace</button><button type="button" id="reset">Reset fixture</button></div><section class="panel"><h2>Fixed application policy</h2><p>Limit 4096 bytes. Count returned bytes, not buffer capacity. Native OpenReadStream needs an explicit maximum and cancellation token.</p></section><footer><p>The evaluator executes an authored byte-count contract, not a C# stream, Blazor integration, upload, or storage operation.</p><p>Use a prepared HTML explanation in <a href="https://nos-workspace.com/">NOS</a> when reviewing this bounded stream-trace evaluator. Eligible static instructions can be revised in visual editing mode; dynamic outputs follow their controls.</p></footer></main><script>
(()=>{'use strict';const $=s=>document.querySelector(s);const out=s=>{$('#result').textContent=s;};const val=id=>$('#'+id).value;const num=id=>{const s=val(id).trim();return s===''?NaN:Number(s);};const on=(id,fn)=>$('#'+id).addEventListener('click',fn);const watch=ids=>{for(const id of ids)for(const event of ['input','change'])$('#'+id).addEventListener(event,()=>out('Inputs changed. Run the action to update this result.'));};const fmt=(n,d=4)=>Math.abs(n)<1e-10?(0).toFixed(d):n.toFixed(d);
(function(){let canceled=false;for(const id of ['chunks','reported'])$('#'+id).addEventListener('input',()=>{canceled=false;out('Trace changed. Evaluate the current record.');});on('cancel',()=>{canceled=true;out('Canceled: no Completed outcome for this trace.');});on('reset',()=>{$('#chunks').value='1024,1024,1024,1024,0';$('#reported').value='100';canceled=false;out('Default trace restored; evaluate again.');});on('evaluate',()=>{if(canceled){out('Canceled: no Completed outcome for this trace.');return;}const raw=val('chunks').split(',').map(s=>s.trim()),reported=num('reported');if(raw.length>100||raw.some(s=>s===''||!Number.isSafeInteger(Number(s))||Number(s)<0)||!Number.isSafeInteger(reported)||reported<0){out('Invalid trace: nonnegative integer counts and metadata required.');return;}let total=0,eof=false;const a=raw.map(Number);for(let i=0;i<a.length;i++){if(eof){out('Invalid trace: returned counts after EOF.');return;}if(a[i]===0){eof=true;continue;}total+=a[i];if(total>4096){out('Rejected: '+total+' counted bytes exceed 4096. Reported Size '+reported+' did not set the limit.');return;}}out(eof?'Completed mock trace: '+total+' bytes and EOF; application limit 4096.':'Reading: '+total+' bytes; EOF not yet observed.');});})();
})();
</script></body></html>