Question

在razor视图中，我可以访问模型状态对象：

prototype

如何在剃刀@ViewData.ModelState中注入和访问ViewData或ModelState个对象？我尝试了以下操作，但TagHelper和ViewData始终为空：

ModelState

Answer 1

对于那些寻找ViewData而不是ModelState的人，您可以将ViewContext添加到TagHelper。

public class EmailTagHelper : TagHelper
{
    [ViewContext]
    public ViewContext ViewContext { get; set; }

    public override async Task ProcessAsync(TagHelperContext context, TagHelperOutput output)
    {
        var hasACertainKey = this.ViewContext.ViewData.ContainsKey("ACertainKey");
    }
}

Answer 2

您可以注入IActionContextAccessor：

    public void ConfigureServices(IServiceCollection services)
    {
        //...
        services.AddSingleton<IActionContextAccessor, ActionContextAccessor>();
    }

    public class ModelStateTagHelper : TagHelper
    {
        public readonly IActionContextAccessor _accessor;

        public ModelStateTagHelper(IActionContextAccessor accessor)
        {
            _accessor = accessor;
        }
        public override void Process(TagHelperContext context, TagHelperOutput output)
        {
            var modelState = _accessor.ActionContext.ModelState;
        }
    }

如何将ViewDataDictionary或ModelStateDictionary注入TagHelper？

2 个答案: