I have a form in mvc where different fields settings are controlled from database.
I have written a razor function which checks if certain fields are mandatory.
In case of true I need to set the required attribute. Currently I can't call razor function in input tag.
What are my options?
<input type="text" class="form-control" asp-for="@Model.Title" required="@myfunction()" maxlength="200" />
You can create a tag helper for this type of situation like below
private const string ForAttributeName = "asp-for";
[HtmlAttributeName("asp-is-required")]
public bool IsMandatory { set; get; }
public InputTextRequired(IHtmlGenerator generator) : base(generator)
{
}
public override void Process(TagHelperContext context, TagHelperOutput output)
{
if (IsMandatory)
{
var attribute = new TagHelperAttribute("required");
output.Attributes.Add(attribute);
}
base.Process(context, output);
}
}
You can use that tag helper in your input tag like below
<input type="text" class="form-control" asp-for="@Model.Title" asp-is-required="true/false from razor" maxlength="200" />
More info on Tag Helper use this link
If I understand correctly, you have your required parameter saved in database, so you can pass it from back end. I would recommend use Viewbag and send it to view from you controller.
Then you can set required tag.
