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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>BLE Printer Test</title>
<script src="https://cdn.jsdelivr.net/npm/iconv-lite-umd@0.6.10/lib/iconv-lite-umd.js"></script>
</head>
<body>
<h1>BLE Printer Test 123</h1>
<button id="printTestButton">Test Print</button>
<button id="printAgain">Print Again</button>
<pre id="log"></pre>
<script>
// Function to log messages on the page
function logMessage(message) {
const logElement = document.getElementById('log');
logElement.textContent += message + '\n';
}
var device;
var server;
var service;
var characteristic;
var name = 'T58_6752'; // 藍芽設備的名稱
var uuid = 0x1800; //service UUID (用 BLE Scanner 找到的)
var characteristicUuid = 0x2A00; // characteristic UUID (用 BLE Scanner 找到的)
// Function to connect to BLE printer and send test data
async function connectAndTestPrint() {
try {
logMessage("Requesting Bluetooth device...");
// Request the BLE device
device = await navigator.bluetooth.requestDevice({
//acceptAllDevices: true,
filters: [
{ name: name }
],
optionalServices: [uuid] // Replace with the correct service UUID
});
logMessage(`Device selected: ${device.name}`);
logMessage(`Device uuid: ${device.id}`);
await printAgain();
} catch (error) {
logMessage(`Error: ${error.message}`);
}
}
// 转码方法
function stringToGbk(str) {
const ranges = [
[0xA1, 0xA9, 0xA1, 0xFE],
[0xB0, 0xF7, 0xA1, 0xFE],
[0x81, 0xA0, 0x40, 0xFE],
[0xAA, 0xFE, 0x40, 0xA0],
[0xA8, 0xA9, 0x40, 0xA0],
[0xAA, 0xAF, 0xA1, 0xFE],
[0xF8, 0xFE, 0xA1, 0xFE],
[0xA1, 0xA7, 0x40, 0xA0],
]
const codes = new Uint16Array(23940)
let i = 0
for (const [b1Begin, b1End, b2Begin, b2End] of ranges) {
for (let b2 = b2Begin; b2 <= b2End; b2++) {
if (b2 !== 0x7F) {
for (let b1 = b1Begin; b1 <= b1End; b1++) {
codes[i++] = b2 << 8 | b1
}
}
}
}
const cstr = new TextDecoder('gbk').decode(codes)
// 编码表
const table = new Uint16Array(65536)
for (let i = 0; i < cstr.length; i++) {
table[cstr.charCodeAt(i)] = codes[i]
}
const buf = new Uint8Array(str.length * 2)
let n = 0
for (let i = 0; i < str.length; i++) {
const code = str.charCodeAt(i)
if (code < 0x80) {
buf[n++] = code
} else {
const gbk = table[code]
buf[n++] = gbk & 0xFF
buf[n++] = gbk >> 8
}
}
u8buf = buf.subarray(0, n)
// console.log(u8buf);
return u8buf
}
async function printAgain() {
// Connect to the GATT server
server = await device.gatt.connect();
logMessage("Connected to GATT server.");
// Get the printer service
service = await server.getPrimaryService(uuid); // Replace with your printer's service UUID
logMessage("Printer service retrieved.");
// Get the characteristic for writing data
characteristic = await service.getCharacteristic(characteristicUuid); // Replace with the correct characteristic UUID
logMessage("Printer characteristic retrieved.");
// Prepare test print data
const encoder = new TextEncoder();
const testData = encoder.encode("TEST PRINT: Hello from Web Bluetooth!\n");
const finalData = encoder.encode("--\n--\n \n \n");
const setFontSize = new Uint8Array([0x1D, 0x21, 0x11]); // GS ! n
const setFontSize2 = new Uint8Array([0x1D, 0x21, 0x22]); // GS ! n
const setFontSize3 = new Uint8Array([0x1D, 0x21, 0x33]); // GS ! n
// Write test data to the printer
logMessage("Sending test data to printer...");
await characteristic.writeValue(new Uint8Array([0x1D, 0x21, 0x00]));
await characteristic.writeValue(encoder.encode("1x1!\n"));
await characteristic.writeValue(setFontSize);
await characteristic.writeValue(encoder.encode("2x2!\n"));
await characteristic.writeValue(setFontSize2);
await characteristic.writeValue(encoder.encode("3x3!\n"));
await characteristic.writeValue(setFontSize3);
await characteristic.writeValue(encoder.encode("4x4!\n"));
const initPrinter = new Uint8Array([0x1B, 0x40]); // ESC @
await characteristic.writeValue(initPrinter);
// 3. 設置字符集為 GBK
const setGBK = new Uint8Array([0x1B, 0x74, 0x11]); // ESC t 0x11 (GBK)
await characteristic.writeValue(setGBK);
const text = "繁體中文測試\n \n";
const encodedText = stringToGbk(text);
await characteristic.writeValue(encodedText);
logMessage("Test data sent successfully!");
// QrCode 列印
const qrData = "https://example.com"; // Your QR code data
const qrDataLength = qrData.length + 3;
const pL = qrDataLength & 0xFF; // Low byte
const pH = (qrDataLength >> 8) & 0xFF; // High byte
const commands = [
0x1B, 0x40, // Initialize printer
0x1D, 0x28, 0x6B, pL, pH, 0x31, 0x50, 0x30, ...new TextEncoder().encode(qrData), // Store data
0x1D, 0x28, 0x6B, 0x03, 0x00, 0x31, 0x51, 0x30 // Print QR code
];
const buffer = new Uint8Array(commands);
await characteristic.writeValue(buffer);
logMessage("QrCode sent successfully!");
await characteristic.writeValue(finalData);
logMessage("finalData sent successfully!");
// Disconnect the GATT server
server.disconnect();
logMessage("Disconnected from printer.");
}
// Bind the function to the button
document.getElementById('printTestButton').addEventListener('click', connectAndTestPrint);
document.getElementById('printAgain').addEventListener('click', printAgain);
</script>
</body>
</html>
Bike, 2025/1/2 下午 02:20:15
可參考本文章:
https://dba.stackexchange.com/questions/245990/postgresql-extremely-slow-count-with-index-simple-query
vacuum analyze insider_event;
執行了 7 分鐘
ALTER TABLE insider_event SET (autovacuum_vacuum_scale_factor = 0, autovacuum_analyze_scale_factor = 0, autovacuum_vacuum_threshold = 10000, autovacuum_analyze_threshold = 10000);
跑了 1.2 分鐘
修改 work_mem:
https://www.pgmustard.com/blog/work-mem
記憶體調整
https://www.enterprisedb.com/postgres-tutorials/how-tune-postgresql-memory
https://dba.stackexchange.com/questions/245990/postgresql-extremely-slow-count-with-index-simple-query
vacuum analyze insider_event;
執行了 7 分鐘
ALTER TABLE insider_event SET (autovacuum_vacuum_scale_factor = 0, autovacuum_analyze_scale_factor = 0, autovacuum_vacuum_threshold = 10000, autovacuum_analyze_threshold = 10000);
跑了 1.2 分鐘
修改 work_mem:
https://www.pgmustard.com/blog/work-mem
記憶體調整
https://www.enterprisedb.com/postgres-tutorials/how-tune-postgresql-memory
Bike, 2024/2/5 上午 06:55:40
Restful 的 API 範例，比較特別的是取得單一筆資料時，不是用一般常見的 {id} 而是用 get?id=xxx 的方式，以避免 XXS 的功擊。(不要把原網頁中的參數拼入 API 網址，要改用 Query String 的方式傳給 API)
再增加一個同步範例(只例出 action)
using Ds;
using Ds.Gv;
using iText.Kernel.Geom;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using NPOI.SS.Formula.Functions;
using NPOI.SS.Util;
using Su;
using System.Linq.Expressions;
namespace CallCampaign.Api
{
/// <summary>
/// 行銷活動
/// </summary>
[Route("api/call-campaign")]
[ApiController]
[SetAuthorizationFilter(Sh.AuthCode.不設限)]
public class ReserveCampaignController : Controller
{
/// <summary>
/// 取得行銷活動列表
/// </summary>
/// <param name="reserveCampaignName"></param>
/// <param name="currentPage"></param>
/// <param name="pageSize"></param>
/// <param name="orderByName"></param>
/// <param name="sort"></param>
/// <returns></returns>
/// <exception cref="Exception"></exception>
[HttpGet("")]
public async Task<object> ListAsync([FromQuery] string reserveCampaignName = "", [FromQuery] int? currentPage = 1, [FromQuery] int? pageSize = 20, [FromQuery] string orderByName = "OrderNo", [FromQuery] string sort = "asc")
{
if (pageSize > 500)
{
pageSize = 500;
}
if (!(sort == "asc" || sort == "desc"))
{
throw new CustomException(System.Net.HttpStatusCode.BadRequest, "sort只能是asc或desc");
}
var temp = new V_ReserveCampaign().GetType().GetProperty(orderByName);
if (temp == null)
{
throw new CustomException(System.Net.HttpStatusCode.BadRequest, "不存在欄位");
}
Expression<Func<V_ReserveCampaign, bool>> q = p => p.Is_Deleted == "N"
&& (string.IsNullOrEmpty(reserveCampaignName) || (p.ReserveCampaignName != null && p.ReserveCampaignName.Contains(reserveCampaignName)))
;
if (orderByName.ToLower().Trim() != "id")
{
orderByName += " " + sort + ", id desc";
}
else
{
orderByName += " " + sort;
}
var ct = NewContext.GvContext;
var list = await ct.GetPageListAsync(q, columns: "Id, ReserveCampaignName, OrderNo, StartAt, EndAt, ModifierName, ModifyDate, CreatorName, CreateDate", page: currentPage ?? 1, pageSize: pageSize ?? 20, orderByName);
//var list = await ct.GetPageListAsync(q, page: currentPage ?? 1, pageSize: pageSize ?? 20, orderByName + " " + sort);
return list;
}
/// <summary>
/// 取得行銷活動
/// </summary>
/// <param name="Id"></param>
/// <returns></returns>
/// <exception cref="Exception"></exception>
[HttpGet("get")]
public async Task<dynamic> GetAsync([FromQuery] int Id)
{
var res = await Ds.NewContext.GvContext.ReserveCampaigns.Where(r => r.Id == Id)
.FirstOrDefaultAsync();
if (res == null)
{
throw new CustomException(System.Net.HttpStatusCode.BadRequest, "查無資料 " + Id.ToString());
}
return res;
}
/// <summary>
/// 建立行銷活動
/// </summary>
/// <param name="dto"></param>
/// <returns></returns>
/// <exception cref="CustomException"></exception>
[HttpPost("")]
public async Task<object> CreateAsync(Dtos.CreateReserveCampaign dto)
{
var ct = NewContext.GvContext;
var res = await Models.ReserveCampaignHelper.CreateReserveCampaignAsync(ct, dto);
return res;
}
/// <summary>
/// 編輯行銷活動
/// </summary>
/// <param name="dto"></param>
/// <returns></returns>
/// <exception cref="CustomException"></exception>
[HttpPatch("")]
public async Task<object> UpdateAsync(Dtos.UpdateReserveCampaign dto)
{
var ct = NewContext.GvContext;
var res = await Models.ReserveCampaignHelper.UpdateReserveCampaignAsync(ct, dto);
return res;
}
/// <summary>
/// 刪除行銷活動
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
/// <exception cref="CustomException"></exception>
[HttpDelete("")]
public async Task<object> DeleteAsync([FromQuery] int id)
{
var res = await Ds.NewContext.GvContext.MarkDeleteAsync<Ds.Gv.ReserveCampaign>(id, Sh.ModifyInfo);
return res;
}
}
}
再增加一個同步範例(只例出 action)
/// <summary>
/// 取得列表
/// </summary>
/// <param name="name"></param>
/// <param name="currentPage"></param>
/// <param name="pageSize"></param>
/// <param name="orderByName"></param>
/// <param name="sort"></param>
/// <returns></returns>
[HttpGet("")]
public object List([FromQuery] string name = "", [FromQuery] int? currentPage = 1, [FromQuery] int? pageSize = 20, [FromQuery] string orderByName = "OrderNo", [FromQuery] string sort = "asc")
{
return "";
}
/// <summary>
/// 取得明細資料
/// </summary>
/// <param name="Id"></param>
/// <returns></returns>
/// <exception cref="Exception"></exception>
[HttpGet("get")]
public object Get([FromQuery] int id)
{
return "";
}
/// <summary>
/// 建立
/// </summary>
/// <param name="dto"></param>
/// <returns></returns>
/// <exception cref="CustomException"></exception>
[HttpPost("")]
public object Create(Dtos.PhysicalCheckUpType dto)
{
return "";
}
/// <summary>
/// 編輯
/// </summary>
/// <param name="dto"></param>
/// <returns></returns>
/// <exception cref="CustomException"></exception>
[HttpPatch("")]
public object Update(Dtos.PhysicalCheckUpType dto)
{
return "";
}
/// <summary>
/// 刪除
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
/// <exception cref="CustomException"></exception>
[HttpDelete("")]
public object Delete([FromQuery] int id)
{
return 1;
}
Bike, 2023/12/13 上午 08:54:28
改寫成可輸入多參數，效能也比較好的版本。
以下為測試碼，請自行依照專案需求做修改。
以下為測試碼，請自行依照專案需求做修改。
var root = "C://wdqd/qwewq";
var addPath = @"//\\/fwef/qwf";
var addPath2 = @"5fwfef/qwf";
var addPath3 = @"//fwef/qwf";
var addPath4 = @"\\\fwef/qwf";
var addPath5 = @"\\\\\/fwef/qwf";
var result = root.AddPath(addPath, addPath2, addPath3, addPath4, addPath5);
Console.WriteLine(result);
public static class Helper
{
public static string AddPath(this string value, params string[] addPaths)
{
if (string.IsNullOrEmpty(value))
{
throw new Exception("起始目錄不可以為空字串");
}
if (value.Contains("..") || addPaths.Any(x => x.Contains("..")))
{
throw new Exception($"value: {value}, addPaths: {addPaths.Where(x => x.Contains("..")).ToOneString()} 檔名與路徑不可包含 ..");
}
var paths = addPaths.Select(x => x.Substring(x.FindLastContinuousCharPosition('/', '\\') + 1).SafeFilename()).ToList();
if (paths.Any(x => System.IO.Path.IsPathRooted(x)))
{
throw new Exception("不可併入完整路徑 ..");
}
paths.Insert(0, value.SafeFilename());
return System.IO.Path.Combine(paths.ToArray());
}
public static string ToOneString<T>(this IEnumerable<T> list, string separator = ",")
{
var strList = list.Select(x => x.ToString());
return string.Join(separator, strList);
}
public static int FindLastContinuousCharPosition(this string input, params char[] targets)
{
int lastPosition = -1;
for (int i = 0; i < input.Length; i++)
{
if (targets.Contains(input[i]))
{
lastPosition = i;
}
else
{
break;
}
}
return lastPosition;
}
public static string SafeFilename(this string value)
{
return GetValidFilename(value);
}
public static string GetValidFilename(string value)
{
string ValidFilenameCharacters = @"0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ\-_$.@:/# ";
if (value.Contains(".."))
{
throw new Exception("路徑中不可包含 .. ");
}
string newUrl = "";
for (int i = 0; i < value.Length; i++)
{
var c = value.Substring(i, 1);
int k = ValidFilenameCharacters.IndexOf(c);
if (k < 0)
{
throw new Exception($"檔名 '{value}' 中有非法的字元 '" + c + "'。");
}
newUrl += ValidFilenameCharacters.Substring(k, 1);
}
return newUrl;
}
}
梨子, 2023/8/28 上午 09:43:49
最近因為資安公司要求，要把 jQuery 升級到最新版
網路查了一下，似乎 3.5 版以後, XSS 才算是改善很多
目前最新版本是 3.7.0，對於原本就使用 3 以上版本專案影響就不大，所有 function 沿用上沒有問題
但是有些舊專案使用 2.X 甚至 1.X 升級到 3.7.0 版之後就會有些功能掛掉
經測試，首當其衝的就是 $(window).load 不能使用，更精準一點應該是 .load() 不能使用
檢查 jquery 過期網頁 https://api.jquery.com/category/deprecated/
發現 .load() 是 1.8 版以後 deprecated，但我 2.2.4 用很久用爽爽
我想應該是 jquery 為了相容問題，一直到跨版本才真的拿掉
也就是 1.X 宣告 deprecated 的功能，到 3.X 才真的移除
(請看附圖)
所以我就鴕鳥的找 1.X deprecated 然後可能會用的 function 處理
(若有 tag "Removed" 就是已移除，這樣找比較快)
大致上專案搜尋字串應該就能處理
但有些可能是其他第三方 jquery物件 例如 jquery-ui ，會用到以上功能
這時可能要去該物件看有無對應升級版
網路查了一下，似乎 3.5 版以後, XSS 才算是改善很多
目前最新版本是 3.7.0，對於原本就使用 3 以上版本專案影響就不大，所有 function 沿用上沒有問題
但是有些舊專案使用 2.X 甚至 1.X 升級到 3.7.0 版之後就會有些功能掛掉
經測試，首當其衝的就是 $(window).load 不能使用，更精準一點應該是 .load() 不能使用
檢查 jquery 過期網頁 https://api.jquery.com/category/deprecated/
發現 .load() 是 1.8 版以後 deprecated，但我 2.2.4 用很久用爽爽
我想應該是 jquery 為了相容問題，一直到跨版本才真的拿掉
也就是 1.X 宣告 deprecated 的功能，到 3.X 才真的移除
(請看附圖)
所以我就鴕鳥的找 1.X deprecated 然後可能會用的 function 處理
(若有 tag "Removed" 就是已移除，這樣找比較快)
.andSelf()
.live()
.die()
.error()
.load()
.unload()
.size()
.toggle()
大致上專案搜尋字串應該就能處理
但有些可能是其他第三方 jquery物件 例如 jquery-ui ，會用到以上功能
這時可能要去該物件看有無對應升級版
darren, 2023/7/20 上午 11:08:33
Entity Framework 提供了 ExecuteSqlRawAsync 和 FromSqlRaw 之後，可以和 Dapper 非常類似的用法。
我們在用 Dapper 時。最常用的就是 sql command 加上一個物件做為參數，就可以執行 CRUD 的動作。
其實用 Entity Framework 的 ExecuteSqlRawAsync 和 FromSqlRaw 也可以逹到幾乎一樣的效果。
ExecuteSqlRawAsync 和 FromSqlRaw 接受的參數是 object array (其實是 Microsoft.Data.SqlClient.SqlParameter 的 array)
所以我們先做一個 Object to Microsoft.Data.SqlClient.SqlParameter Array 的擴充, 可參考: https://gist.github.com/aliozgur/75182b2e9b0a58b83443
不過很奇怪的是，原作者提供的擴充轉出來的會是 System.Data.SqlClient.SqlParameter Array 無法直接使用於 ExecuteSqlRawAsync 和 FromSqlRaw，所以要稍微改一下，把 using System.Data.SqlClient; 改為 using Microsoft.Data.SqlClient; 即可:
另外，我們再自行 對 DbContext 做一個擴充如下:
最後的結果可以做到以下的效果: (res3 和 res4 是配合 FormattableString 的範例 )
範例程式碼:
我們在用 Dapper 時。最常用的就是 sql command 加上一個物件做為參數，就可以執行 CRUD 的動作。
其實用 Entity Framework 的 ExecuteSqlRawAsync 和 FromSqlRaw 也可以逹到幾乎一樣的效果。
ExecuteSqlRawAsync 和 FromSqlRaw 接受的參數是 object array (其實是 Microsoft.Data.SqlClient.SqlParameter 的 array)
所以我們先做一個 Object to Microsoft.Data.SqlClient.SqlParameter Array 的擴充, 可參考: https://gist.github.com/aliozgur/75182b2e9b0a58b83443
不過很奇怪的是，原作者提供的擴充轉出來的會是 System.Data.SqlClient.SqlParameter Array 無法直接使用於 ExecuteSqlRawAsync 和 FromSqlRaw，所以要稍微改一下，把 using System.Data.SqlClient; 改為 using Microsoft.Data.SqlClient; 即可:
另外，我們再自行 對 DbContext 做一個擴充如下:
/// <summary>
/// 會把物件 Parameter 的各 Property 帶入 SQL 中.
/// </summary>
/// <param name="dbct"></param>
/// <param name="sql"></param>
/// <param name="parameters"></param>
/// <returns></returns>
public static async Task<int> ExecuteParameterSqlAsync(this DbContext dbct, string sql, object parameters)
{
return await dbct.Database.ExecuteSqlRawAsync(sql, parameters.ToSqlParamsArray());
}
最後的結果可以做到以下的效果: (res3 和 res4 是配合 FormattableString 的範例 )
範例程式碼:
public async Task<object> EfTest()
{
var dbct = Ds.NewContext.GvContext;
var insertSql = @"Insert into ProfileEvent(JobId,[Name],GvShoplineId,LiShoplineId,Phone,Email,LineId,GaClientId)
Values(@JobId, @Name, null , null , null , @Email, @GaClientId , @GaClientId )";
//執行 SQL 的原生寫法
await dbct.Database.ExecuteSqlRawAsync(insertSql, new object[]
{
new SqlParameter("@JobId", 10),
new SqlParameter("@Email", "XX'TT"),
new SqlParameter("@Name", "AA'BB"),
new SqlParameter("@GaClientId", "GaClientId"),
});
//執行 SQL 的擴充寫法
await dbct.ExecuteParameterSqlAsync(insertSql, new
{
JobId = 10,
Email = "XX'TT",
Name = "AA'BB",
GaClientId = "GaClientId"
});
//關於查詢
string name = "%'B%";
//原生寫法
var res1 = await dbct.ProfileEvents.FromSqlRaw("Select top 100 * from ProfileEvent where Name like @name",
new object[]
{
new SqlParameter("@name", "%'B%")
})
.ToListAsync();
//擴充, object to SqlParameter array
var res2 = await dbct.ProfileEvents.FromSqlRaw("Select top 100 * from ProfileEvent where Name like @name",
new { name }.ToSqlParamsArray())
.ToListAsync();
var res3 = await dbct.ProfileEvents.FromSql($"Select top 100 * from ProfileEvent where Name like {name}")
.ToListAsync();
var res4 = await dbct.ProfileEvents.FromSqlInterpolated($"Select top 100 * from ProfileEvent where Name like {name}")
.ToListAsync();
return new { res1, res2, res3, res4 };
}
Bike, 2023/5/6 下午 05:37:19
產生 FileStreamResult 物件的 function 如下: (目前置於 SU 之中，以便轉移)
輸出用的 Controller 和 Action 如下:
static List<Brush> CaptchaBrushes = null;
public static FileStreamResult CreateCaptcha(string captcha)
{
if (CaptchaBrushes == null)
{
CaptchaBrushes = new List<Brush>();
CaptchaBrushes.Add(Brushes.White);
CaptchaBrushes.Add(Brushes.Gold);
CaptchaBrushes.Add(Brushes.LightSkyBlue);
CaptchaBrushes.Add(Brushes.LimeGreen);
CaptchaBrushes.Add(Brushes.AliceBlue);
CaptchaBrushes.Add(Brushes.AntiqueWhite);
CaptchaBrushes.Add(Brushes.BurlyWood);
CaptchaBrushes.Add(Brushes.Silver);
}
int width = 90;
int height = 45;
//https://stackoverflow.com/questions/61365732/cannot-access-a-closed-stream-when-returning-filestreamresult-from-c-sharp-netc
//Using statements close and unload the variable from memory set in the using statement which is why you are getting an error trying to access a closed memory stream.You don't need to use a using statement if you are just going to return the result at the end.
//這個 memory stream 不用關閉或 dispose
var ms = new MemoryStream();
// 釋放所有在 GDI+ 所佔用的記憶體空間 ( 非常重要!! )
using (Bitmap _bmp = new Bitmap(width, height))
using (Graphics _graphics = Graphics.FromImage(_bmp))
using (Font _font = new Font("Courier New", 24, FontStyle.Bold)) // _font 設定要出現在圖片上的文字字型、大小與樣式
{
// (封裝 GDI+ 繪圖介面) 所有繪圖作業都需透過 Graphics 物件進行操作
_graphics.Clear(Color.Black);
// 如果想啟用「反鋸齒」功能，可以將以下這行取消註解
//_graphics.TextRenderingHint = TextRenderingHint.AntiAlias;
// 將亂碼字串「繪製」到之前產生的 Graphics 「繪圖板」上
var x = 10;
for(var i = 0; i < captcha.Length; i++)
{
_graphics.DrawString(captcha.Substring(i, 1), _font, CaptchaBrushes[Su.MathUtil.GetRandomInt(CaptchaBrushes.Count)], x, Su.MathUtil.GetRandomInt(15));
x += 10 + Su.MathUtil.GetRandomInt(10);
}
// 畫線
_graphics.DrawLine(new Pen(CaptchaBrushes[Su.MathUtil.GetRandomInt(CaptchaBrushes.Count)], 1),
Su.MathUtil.GetRandomInt(0, Convert.ToInt32((width * 0.9 / 2))), 0, Su.MathUtil.GetRandomInt(Convert.ToInt32(width / 2), Convert.ToInt32(width * 1.9 / 2)), height);
_graphics.DrawLine(new Pen(CaptchaBrushes[Su.MathUtil.GetRandomInt(CaptchaBrushes.Count)], 1),
Su.MathUtil.GetRandomInt(Convert.ToInt32(width / 2), Convert.ToInt32(width * 1.9 / 2)), 0, Su.MathUtil.GetRandomInt(0, Convert.ToInt32((width * 0.9 / 2))), height);
_graphics.DrawLine(new Pen(CaptchaBrushes[Su.MathUtil.GetRandomInt(CaptchaBrushes.Count)], 1),
0,
Su.MathUtil.GetRandomInt(height / 2),
width,
height / 2 + Su.MathUtil.GetRandomInt(height / 2)
);
_graphics.DrawLine(new Pen(CaptchaBrushes[Su.MathUtil.GetRandomInt(CaptchaBrushes.Count)], 1),
0,
height / 2 + Su.MathUtil.GetRandomInt(height / 2),
width,
Su.MathUtil.GetRandomInt(height / 2)
);
_bmp.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
}
ms.Seek(0, SeekOrigin.Begin);
// Controller 的型別為 FileResult
return new FileStreamResult(ms, "image/jpeg")
{ FileDownloadName = $"{DateTime.Now.Ymdhmsf()}.jpg" };
}
輸出用的 Controller 和 Action 如下:
namespace Web.Controllers
{
public class CaptchaController : Controller
{
[Route("captcha")]
public async Task<FileStreamResult> Index()
{
//產生 Captcha 並存入 Session 之中。目前是四位數字
string captcha = (await Ah.ReGetAsync<object>("api/kol/create-captcha-code")).ToString();
//產生圖檔並回傳 FileStreamResult
return Su.Wu.CreateCaptcha(captcha);
}
}
}
Bike, 2022/9/25 下午 10:03:44
static System.Security.Cryptography.RandomNumberGenerator RandomNumberGenerator = null;
/// <summary>
/// 回傳大於等於 0 小於 1
/// </summary>
/// <returns></returns>
public static double NextDouble()
{
if (RandomNumberGenerator == null || LastRandomGenerateTime < DateTime.Now.AddMinutes(-1))
{
RandomNumberGenerator = System.Security.Cryptography.RandomNumberGenerator.Create();
}
// Generate four random bytes
byte[] four_bytes = new byte[4];
RandomNumberGenerator.GetBytes(four_bytes);
// Convert the bytes to a UInt32
uint scale = BitConverter.ToUInt32(four_bytes, 0);
// And use that to pick a random number >= min and < max
// 0 <= (scale / (uint.MaxValue + 1.0)) < 1
return scale / (uint.MaxValue + 1.0);
}
/// <summary>
/// 回傳值介於 min ~ (max - 1)
/// </summary>
/// <param name="min"></param>
/// <param name="max"></param>
/// <returns></returns>
public static int GetRandomInt(int min, int max)
{
if(max < min)
{
throw new Exception("最大值不可小於最小值");
}
// Generate four random bytes
byte[] four_bytes = new byte[4];
RandomNumberGenerator.GetBytes(four_bytes);
// And use that to pick a random number >= min and < max
return (int)(min + (max - min) * NextDouble()); //因為 NextDouble 會小於 1，所以用無條件捨去.
}
/// <summary>
/// 產生 0 ~ (max - 1) 的亂數
/// </summary>
/// <param name="max"></param>
/// <returns></returns>
public static int GetRandomInt(int max)
{
return GetRandomInt(0, max);
}
/// <summary>
/// 產生 0 ~ (int.MaxValue - 1) 的亂數
/// </summary>
/// <returns></returns>
public static int GetRandomInt()
{
return GetRandomInt(int.MaxValue);
}
Bike, 2022/9/22 下午 08:30:03
在 Postgres 使用 TransactionScope 似乎很空易就會發生 Transaction Abort 的情況。所以必需自行實做 retry 的機制
int tries = 0;
while (tries < Su.PgSql.maxTransactionAborted)
{
try
{
using (var scop = new System.Transactions.TransactionScope(TransactionScopeAsyncFlowOption.Enabled))
{
var context = ShopBandContext.Context;
updateCount = await context.UpdateAsync<MarketDiscount>(dto, Sc.ModifyInfo,
onlyColumns: "StartAt,EndAt,NewPrice,FrontEndMemo,BackEndMemo");
scop.Complete();
break; //這個 Break 很重要
}
}
catch (Exception ex)
{
// 我發現因為是非同步模式，所以要檢查很多層的 InnerException
if (tries < Su.PgSql.maxTransactionAborted
&& ((ex.InnerException != null && ex.InnerException is Npgsql.PostgresException && ((Npgsql.PostgresException)ex.InnerException).SqlState == "40001")
|| (ex.InnerException.InnerException != null && ex.InnerException.InnerException is Npgsql.PostgresException && ((Npgsql.PostgresException)ex.InnerException.InnerException).SqlState == "40001")))
{
//隨機休息 10 ~ 20 ms, 等另一個 job 完工
System.Threading.Thread.Sleep(Su.MathUtil.Random.Next(10, 20));
tries++;
}
else
{
throw;
}
}
}
Bike, 2022/8/25 上午 09:19:35
--建立 table (要記得改 XXX)
CREATE TABLE IF NOT EXISTS public.table_monitor
(
table_name text COLLATE pg_catalog."default" NOT NULL,
update_at timestamp without time zone NOT NULL DEFAULT now(),
update_count bigint NOT NULL DEFAULT 0,
CONSTRAINT table_monitor_pkey PRIMARY KEY (table_name)
)
TABLESPACE pg_default;
ALTER TABLE IF EXISTS public.table_monitor
OWNER to XXX;
-- 這一段只要執行一次
CREATE OR REPLACE FUNCTION public.table_monitor_trigger_fnc()
RETURNS trigger
LANGUAGE 'plpgsql'
COST 100
VOLATILE NOT LEAKPROOF
AS $BODY$
BEGIN
Update public.table_monitor Set update_count = update_count + 1, update_at = now() Where table_name = TG_TABLE_NAME;
RETURN NEW;
END;
$BODY$;
ALTER FUNCTION public.table_monitor_trigger_fnc()
OWNER TO XXX;
-- 對於被監控的 table, 要執行以下的指令，記得 xxxx 要改為 table 的名字(要符合大小寫)
INSERT INTO public.table_monitor (table_name, update_at, update_count) VALUES ('xxxx', '2000-01-01', 0) ON CONFLICT DO NOTHING;
CREATE OR REPLACE TRIGGER table_monitor_trigger
AFTER INSERT OR DELETE OR UPDATE
ON xxxx
FOR EACH STATEMENT
EXECUTE FUNCTION public.table_monitor_trigger_fnc();
監控用的程式碼:
CREATE TABLE IF NOT EXISTS public.table_monitor
(
table_name text COLLATE pg_catalog."default" NOT NULL,
update_at timestamp without time zone NOT NULL DEFAULT now(),
update_count bigint NOT NULL DEFAULT 0,
CONSTRAINT table_monitor_pkey PRIMARY KEY (table_name)
)
TABLESPACE pg_default;
ALTER TABLE IF EXISTS public.table_monitor
OWNER to XXX;
-- 這一段只要執行一次
CREATE OR REPLACE FUNCTION public.table_monitor_trigger_fnc()
RETURNS trigger
LANGUAGE 'plpgsql'
COST 100
VOLATILE NOT LEAKPROOF
AS $BODY$
BEGIN
Update public.table_monitor Set update_count = update_count + 1, update_at = now() Where table_name = TG_TABLE_NAME;
RETURN NEW;
END;
$BODY$;
ALTER FUNCTION public.table_monitor_trigger_fnc()
OWNER TO XXX;
-- 對於被監控的 table, 要執行以下的指令，記得 xxxx 要改為 table 的名字(要符合大小寫)
INSERT INTO public.table_monitor (table_name, update_at, update_count) VALUES ('xxxx', '2000-01-01', 0) ON CONFLICT DO NOTHING;
CREATE OR REPLACE TRIGGER table_monitor_trigger
AFTER INSERT OR DELETE OR UPDATE
ON xxxx
FOR EACH STATEMENT
EXECUTE FUNCTION public.table_monitor_trigger_fnc();
監控用的程式碼:
public static void UpdateTableCache()
{
//標記自已是正在執行的 Thread. 讓舊的 Thread 在執行完畢之後, 應該會自動結束. 以防舊的 Thread 執行超過 10 秒.
CurrentThreadId = System.Threading.Thread.CurrentThread.ManagedThreadId;
try
{
//確認自已是正在執行的 Thread, 重覆執行. (另一個 Thread 插入執行)
while (CurrentThreadId == System.Threading.Thread.CurrentThread.ManagedThreadId)
{
LastUpdateDate = DateTime.Now;
foreach (var dbId in CachedDbs)
{
var sql = @"select * from table_monitor";
var dt = Su.PgSql.DtFromSql(sql, dbId);
foreach (DataRow row in dt.Rows)
{
string changeId = row["update_count"].DBNullToDefault();
string CacheKey = TableCacheKey(dbId, row["table_name"].DBNullToDefault());
ObjectCache cache = MemoryCache.Default;
string OldValue = (string)cache[CacheKey];
if (OldValue == null)
{
cache.Set(CacheKey, changeId, DateTime.MaxValue);
}
else
{
if (changeId != OldValue)
{
cache.Remove(CacheKey);
cache.Set(CacheKey, changeId, DateTime.MaxValue);
}
}
}
}
//每兩秒檢查一次
System.Threading.Thread.Sleep(2000);
}
}
catch (Exception)
{
//依經驗, 只要 DB 能通, 這裡幾乎不會有問題, 所以這裡暫時不處理, 未來有問題時可以考慮寫入文字檔比較好.
}
}
Bike, 2022/7/20 上午 10:05:39