| | | 1 | | @using System.Linq; |
| | | 2 | | |
| | | 3 | | <div class="container"> |
| | | 4 | | <div class="row"> |
| | | 5 | | <div class="col"> |
| | | 6 | | <div class="input-group"> |
| | | 7 | | <input id="luhnCheck" name="luhnCheck" class="form-control" @bind="check" placeholder="378282246310005" |
| | | 8 | | <span class="input-group-btn"> |
| | | 9 | | <button id="btnLuhnCheckClear" name="btnLuhnCheckClear" class="btn btn-danger float-right" @onclick= |
| | | 10 | | </span> |
| | | 11 | | </div> |
| | | 12 | | </div> |
| | | 13 | | </div> |
| | | 14 | | <div class="row"> |
| | | 15 | | <div class="col"> |
| | | 16 | | <button id="btnLuhnCheck" name="btnLuhnCheck" class="btn btn-success float-right" @onclick="CheckSingle">Che |
| | | 17 | | </div> |
| | | 18 | | </div> |
| | | 19 | | <div class="row"> |
| | | 20 | | <div class="col"> |
| | | 21 | | <label class="label-control">Valid?</label> |
| | | 22 | | <label class="label-control" id="luhnCheckLabel">@valid.ToString()</label> |
| | | 23 | | </div> |
| | | 24 | | </div> |
| | | 25 | | @*<div class="row"> |
| | | 26 | | <textarea id="luhnChecks" class="form-control" @bind="checks"></textarea> |
| | | 27 | | </div> |
| | | 28 | | <div class="row"> |
| | | 29 | | <button id="btnLuhnChecks" name="btnLuhnChecks" class="btn btn-success float-right" |
| | | 30 | | @onclick="CheckMultiple"> |
| | | 31 | | Check |
| | | 32 | | </button> |
| | | 33 | | <button id="btnLuhnChecksClear" name="btnLuhnChecksClear" class="btn btn-danger float-right" |
| | | 34 | | @onclick="ClearMultiple"> |
| | | 35 | | <i class="far fa-trash-alt"></i> |
| | | 36 | | </button> |
| | | 37 | | </div>*@ |
| | | 38 | | </div> |
| | | 39 | | |
| | | 40 | | @code { |
| | | 41 | | |
| | | 42 | | [Parameter] |
| | 12 | 43 | | public string check { get; set; } |
| | | 44 | | |
| | | 45 | | [Parameter] |
| | 12 | 46 | | public bool valid { get; set; } |
| | | 47 | | //string checks; |
| | | 48 | | |
| | | 49 | | protected override async Task OnInitializedAsync() |
| | 2 | 50 | | { |
| | | 51 | | // check = "378282246310005"; //string.Empty; |
| | 2 | 52 | | valid = false; |
| | | 53 | | // valid = LuhnCheck(check); |
| | | 54 | | //checks = "b"; //string.Empty; |
| | 2 | 55 | | } |
| | | 56 | | |
| | | 57 | | private void CheckSingle() |
| | 2 | 58 | | { |
| | 2 | 59 | | valid = LuhnCheck(check); |
| | 2 | 60 | | } |
| | | 61 | | |
| | | 62 | | private void ClearSingle() |
| | 0 | 63 | | { |
| | 0 | 64 | | check = string.Empty; |
| | 0 | 65 | | } |
| | | 66 | | |
| | | 67 | | @*private void CheckMultiple() |
| | | 68 | | { |
| | | 69 | | var valid = LuhnCheck(check); |
| | | 70 | | } |
| | | 71 | | |
| | | 72 | | private void ClearMultiple() |
| | | 73 | | { |
| | | 74 | | checks = string.Empty; |
| | | 75 | | }*@ |
| | | 76 | | |
| | | 77 | | // https://stackoverflow.com/a/40491537 |
| | | 78 | | private static bool LuhnCheck(string digits) |
| | 2 | 79 | | { |
| | 2 | 80 | | if (string.IsNullOrEmpty(digits)) return false; |
| | | 81 | | |
| | 2 | 82 | | return digits.All(char.IsDigit) && digits.Reverse() |
| | 16 | 83 | | .Select(c => c - 48) |
| | 16 | 84 | | .Select((thisNum, i) => i % 2 == 0 |
| | 16 | 85 | | ? thisNum |
| | 16 | 86 | | : ((thisNum *= 2) > 9 ? thisNum - 9 : thisNum) |
| | 2 | 87 | | ).Sum() % 10 == 0; |
| | 2 | 88 | | } |
| | | 89 | | } |