将特殊字符分配给字符串时，剃刀页面弄乱了编码

Question

更新 4：

哇哦，显然这不是 EF 或配置问题。

Somehow the .razor page variable assigment is messing up the data.

现在不知道如何处理这个问题，但我至少编辑了标题以反映当前问题，即：Razor page is messing up the encoding when assignment special character to string.

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问题：

无论我做什么，我插入 MySQL 5.7.17 数据库的字符总是显示为 �:

Database lookup

虽然有类似的帖子，但没有一个解决方案对我有用，我已经用尽了我的研究能力。

我尝试过的：

• 连接字符串上的“charset=utf8mb4”和“SET character_set_connection” SQL 命令： When using Entity Framework with MySQL, Unicode characters are replaced with basic characters

• 使用“utf8mb4”： MySQL charset=UTF-8 with ConnectionReset=True is not working

• 像 [MySqlCharset("utf8mb4")] 的数据注解：https://dev.mysql.com/doc/connector-net/en/connector-net-entityframework-core-charset.html

• 查询值的前缀 N： MySQL C# Text Encoding Problems

• 准备好的声明
• 在“OnModelCreating”上使用“IsUnicode(true)”

代码：

连接字符串：

"MySQL": "server=localhost;user=root;database=sgn;charset=utf8mb4;"

UserModel.cs

namespace source.Data.Models
{
    [MySqlCharset("utf8mb4")]
    [MySqlCollation("utf8mb4_unicode_ci")]
    public class UserModel
    {
        public UserModel() { }

        [Key]
        public long Id { get; set; }
        [MySqlCharset("utf8mb4")]
        [MySqlCollation("utf8mb4_unicode_ci")]
        public string Username { get; set; }
        public string Email { get; set; }
        public string Password { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Language { get; set; }
        public string StartPage { get; set; }
    }
}

DatabaseContext.cs

namespace source.Data.Database
{
    public class DatabaseContext : DbContext
    {
        private IConfiguration Configuration;
        public DbSet<UserModel> Users { get; set; }

        public DatabaseContext(DbContextOptions<DatabaseContext> options, IConfiguration configuration)
            : base(options)
        {
            Configuration = configuration;
        }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            optionsBuilder
                .UseMySQL(Configuration.GetSection("AppSettings").GetSection("Database").GetSection("ConnectionString")["MySQL"]);
        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<UserModel>().Property(p => p.Username).IsUnicode(true);
            base.OnModelCreating(modelBuilder);
        }

    }
}

DesignTimeDatabaseContextFactory.cs

namespace source.Data.Database
{
    public class DesignTimeDatabaseContextFactory : IDesignTimeDbContextFactory<DatabaseContext>
    {
        private IConfiguration Configuration;
        private AppSettingsService AppSettings;

        public DesignTimeDatabaseContextFactory()
        {
        }

        public DesignTimeDatabaseContextFactory(IConfiguration configuration, AppSettingsService appSettings)
        {
            Configuration = configuration;
            AppSettings = appSettings;
        }

        public DatabaseContext CreateDbContext(string[] args)
        {
            var builder = new DbContextOptionsBuilder<DatabaseContext>();

            builder.UseMySQL(AppSettings.ConnectionString);


            return new DatabaseContext(builder.Options, Configuration);
        }
    }
}

Create.razor - 这是我将用户添加到数据库的地方。请注意，此项目使用 Blazor，因此不要被“@functions”标签混淆。这两个函数都没有正确添加数据，并且注释的是我尝试过的准备好的语句。

<div class="login_form">
    <h3>Create Account</h3>

    <button @onclick="@(e => AddEntry())">Add DB User!</button><br />
    <button @onclick="@(e => AddEntry2())">Add TEST!</button><br />
</div>

@functions {

    void AddEntry2()
    {
        UserModel test = new UserModel();

        test.Username = "Test çã";
        test.FirstName = "Michel";
        test.LastName = "Arendt";
        test.Email = "mail@gmail.com";
        test.Password = "123";
        test.Language = "pt-BR";
        test.StartPage = "/Home/";

        db.Database.ExecuteSqlCommand("SET NAMES utf8mb4");
        db.Database.ExecuteSqlCommand("SET character_set_connection = utf8mb4");
        db.Database.ExecuteSqlCommand("INSERT INTO Users (Username) VALUES (N'" + test.Username + "')");
        db.SaveChanges();


        //using (SqlConnection connection = new SqlConnection(AppSettings.DatabaseConnectionString()))
        //{
        //    connection.Open();
        //    SqlCommand command = new SqlCommand(null, connection);

        //    // Create and prepare an SQL statement.
        //    command.CommandText =
        //        "INSERT INTO Users (Username) " +
        //        "VALUES (@username)";
        //    SqlParameter username = new SqlParameter("@username", SqlDbType.NVarChar, 100);
        //    username.Value = "Garçon";
        //    command.Parameters.Add(username);

        //    // Call Prepare after setting the Commandtext and Parameters.
        //    command.Prepare();
        //    command.ExecuteNonQuery();
        //}
    }

    void AddEntry()
    {
        UserModel waitress = new UserModel();

        waitress.Username = "Garçon";
        waitress.FirstName = "Test";
        waitress.LastName = "Test";
        waitress.Email = "mail@gmail.com";
        waitress.Password = "123";
        waitress.Language = "pt-BR";
        waitress.StartPage = "/Home/";

        db.Users.Add(waitress);
        db.SaveChanges();
    }
}

source.csproj（依赖项参考）

<Project Sdk="Microsoft.NET.Sdk.Web">
  <PropertyGroup>
    <TargetFramework>netcoreapp3.0</TargetFramework>
    <LangVersion>7.3</LangVersion>
    <RestorePackages>false</RestorePackages>
    <Version>0.10.0</Version>
    <Authors>Michel Arendt</Authors>
    <Product>SGN</Product>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
    <DefineConstants>DEBUG;TRACE</DefineConstants>
    <DebugType>full</DebugType>
    <DebugSymbols>true</DebugSymbols>
  </PropertyGroup>
  <ItemGroup>
    <Content Remove="compilerconfig.json" />
  </ItemGroup>
  <ItemGroup>
    <None Include="compilerconfig.json" />
  </ItemGroup>
  <ItemGroup>
    <PackageReference Include="ElectronNET.API" Version="5.22.13" />
    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="2.2.4" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="2.2.4" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="2.2.4">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
    </PackageReference>
    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="2.2.0" />
    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="3.0.0-preview6.19304.6" />
    <PackageReference Include="Microsoft.Extensions.Options.ConfigurationExtensions" Version="2.2.0" />
    <PackageReference Include="MySql.Data.EntityFrameworkCore" Version="8.0.16" />
    <PackageReference Include="System.Configuration.ConfigurationManager" Version="4.5.0" />
  </ItemGroup>
  <ItemGroup>
    <Content Update="electron.manifest.json">
      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
    </Content>
  </ItemGroup>
</Project>

数据库配置

数据库和列的默认排序规则和字符集分别为 utf8mb4_unicode_ci 和 utf8mb4：

Default database character set and collation

Columns character set and collation

---

对于我还可以尝试什么来解决此问题或我正在犯什么错误有什么想法吗？

提前致谢！

---

更新：

按照 Bradley Grainger（在 cmets 上）的建议，我切换到了 Pomelo.EntityFrameworkCore.MySql，但这无助于解决问题。我更改的文件现在是：

将构建从 Startup.cs 和 DesignTimeDatabaseContextFactory.cs 更改为使用：

builder
                .UseMySql(AppSettings.ConnectionString,
                    mysqlOptions =>
                    {
                        mysqlOptions
                            .CharSetBehavior(CharSetBehavior.AppendToAllColumns)
                            .AnsiCharSet(CharSet.Utf8mb4)
                            .UnicodeCharSet(CharSet.Utf8mb4);
                    });

Create.razor

void AddEntry2()
{
    UserModel test = new UserModel();

    test.Username = "Test çã";
    test.FirstName = "Michel";
    test.LastName = "Arendt";
    test.Email = "mail@gmail.com";
    test.Password = "123";
    test.Language = "pt-BR";
    test.StartPage = "/Home/";

    using (MySqlConnection connection = new MySqlConnection(AppSettings.ConnectionString))
    {
        connection.Open();
        MySqlCommand command = new MySqlCommand(null, connection);

        // Create and prepare an SQL statement.
        command.CommandText =
            "INSERT INTO Users (Username) " +
            "VALUES (@username)";
        MySqlParameter username = new MySqlParameter("@username", MySqlDbType.LongText, 100);
        username.Value = "Garçon";
        command.Parameters.Add(username);

        // Call Prepare after setting the Commandtext and Parameters.
        command.Prepare();
        command.ExecuteNonQuery();
    }
}

认为这会有所帮助，所以我还在本地服务器上设置了 MySQL 初始化 (my.ini) 以：

[mysqld]
character-set-server=utf8mb4
collation-server=utf8mb4_general_ci

但是，没有任何效果。还有其他想法吗？

---

更新 2：

为了确定是数据库还是 EF Core 问题，我设置了一个简单的 PHP 脚本来在数据库中插入相同的条目。

On this image entry 1 and 2 are inserted from EF Core while entry 3 was inserted from PHP

从图像中可以看出，数据库似乎很好，因为 PHP 的插入工作正常。

添加条目时如何确保EF Core使用的是“utf8mb4”编码？

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Answer 1

正如 Thomas Schmidt 在 OP 的 cmets 上所建议的那样，问题出在其他地方，我没有想到 Visual Studio 保存文件时使用的编码。这个问题描述了解决方案：

razor view » character rendered as »

解决方案：

选择您要更改编码的文件并点击文件菜单，然后将“PAGE”另存为，然后选择Save with Encoding...并选择所需的编码。

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我已编辑帖子的问题标题以反映当前问题。让我知道是否应该将其更改回来，因为我不确定如何在此处继续。