Tag: .net

Bind modifiers (@bind:after, @bind:get, @bind:set) in Blazor 7.0

In .NET 7, you can run asynchronous logic after a binding event has completed using the new @bind:after modifier. In the following example, the PerformSearch asynchronous method runs automatically after any changes to the search text are detected:

<input @bind="searchText" @bind:after="PerformSearch" />

@code {
    private string searchText;

    private async Task PerformSearch()
    {
        ...
    }
}

In .NET 7, it’s also easier to set up binding for component parameters. Components can support two-way data binding by defining a pair of parameters:

  • @bind:get: Specifies the value to bind.
  • @bind:set: Specifies a callback for when the value changes.

The @bind:get and @bind:set modifiers are always used together.

Example:

<input @bind:get="Value" @bind:set="ValueChanged" />

@code {
    [Parameter]
    public TValue? Value { get; set; }

    [Parameter]
    public EventCallback<TValue> ValueChanged { get; set; }
}

References
https://learn.microsoft.com/en-us/aspnet/core/release-notes/aspnetcore-7.0?view=aspnetcore-7.0#bind-modifiers-bindafter-bindget-bindset

Component Parameter Binding in Blazor 7.0

In prior Blazor releases, binding across multiple components required binding to properties with get/set accessors.

In .NET 6 and earlier:

<NestedGrandchild @bind-GrandchildMessage="BoundValue" />

@code {
    ...

    private string BoundValue
    {
        get => ChildMessage ?? string.Empty;
        set => ChildMessageChanged.InvokeAsync(value);
    }
}

In .NET 7, you can use the new @bind:get and @bind:set modifiers to support two-way data binding and simplify the binding syntax:

<NestedGrandchild @bind-GrandchildMessage:get="ChildMessage" 
    @bind-GrandchildMessage:set="ChildMessageChanged" />

References
https://learn.microsoft.com/en-us/aspnet/core/migration/60-70?view=aspnetcore-7.0&tabs=visual-studio#simplify-component-parameter-binding
https://pupli.net/2022/01/two-way-binding-in-blazor-component/

Get Table and Columns Name of mapped entity in Entity Framework Core

var context = new BiContext();

var entityType = context.Model.FindEntityType(typeof(InvoiceDetail));

var tableName = entityType.GetTableName();
Console.WriteLine(tableName);
var properties = entityType.GetProperties();

# Property Name in Class
foreach (var p in properties)
{
    Console.WriteLine(p.Name);
}

# Column Name in Table
foreach (var p in properties)
{
    Console.WriteLine(p.GetColumnName());
}

References
https://stackoverflow.com/questions/45667126/how-to-get-table-name-of-mapped-entity-in-entity-framework-core

Read characters from a string in C#

using System;
using System.IO;

public class CharsFromStr
{
    public static void Main()
    {
        string str = "Some number of characters";
        char[] b = new char[str.Length];

        using (StringReader sr = new StringReader(str))
        {
            // Read 13 characters from the string into the array.
            sr.Read(b, 0, 13);
            Console.WriteLine(b);

            // Read the rest of the string starting at the current string position.
            // Put in the array starting at the 6th array member.
            sr.Read(b, 5, str.Length - 13);
            Console.WriteLine(b);
        }
    }
}
// The example has the following output:
//
// Some number o
// Some f characters

References
https://learn.microsoft.com/en-us/dotnet/standard/io/how-to-read-characters-from-a-string

Configuration options for the dependabot.yml for .net Projects

# generated by dependadotnet
# https://github.com/dotnet/core/tree/main/samples/dependadotnet
version: 2
updates:
  - package-ecosystem: "nuget"
    directory: "/azure/sdk-identity-resources-storage" #AzureIdentityStorageExample.csproj
    schedule:
      interval: "weekly"
      day: "wednesday"
    open-pull-requests-limit: 5
  - package-ecosystem: "nuget"
    directory: "/csharp/expression-trees" #expression-trees.csproj
    schedule:
      interval: "weekly"
      day: "wednesday"
    open-pull-requests-limit: 5
  - package-ecosystem: "nuget"
    directory: "/core/assembly/MetadataLoadContext" #MetadataLoadContextSample.csproj
    schedule:
      interval: "weekly"
      day: "wednesday"
    open-pull-requests-limit: 5

References
https://docs.github.com/en/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file
https://github.com/dotnet/samples/blob/main/.github/dependabot.yml