Best way to trim strings after data entry. Should

Question

I'm using ASP.NET MVC and I'd like all user entered string fields to be trimmed before they're inserted into the database. And since I have many data entry forms, I'm looking for an elegant way to trim all strings instead of explicitly trimming every user supplied string value. I'm interested to know how and when people are trimming strings.

I thought about perhaps creating a custom model binder and trimming any string values there...that way, all my trimming logic is contained in one place. Is this a good approach? Are there any code samples that do this?

Answer 1

This is @takepara same resolution but as an IModelBinder instead of DefaultModelBinder so that adding the modelbinder in global.asax is through

ModelBinders.Binders.Add(typeof(string),new TrimModelBinder());

The class:

public class TrimModelBinder : IModelBinder
{
    public object BindModel(ControllerContext controllerContext,
    ModelBindingContext bindingContext)
    {
        ValueProviderResult valueResult = bindingContext.ValueProvider.GetValue(bindingContext.ModelName);
        if (valueResult== null || valueResult.AttemptedValue==null)
           return null;
        else if (valueResult.AttemptedValue == string.Empty)
           return string.Empty;
        return valueResult.AttemptedValue.Trim();
    }
}

based on @haacked post: http://haacked.com/archive/2011/03/19/fixing-binding-to-decimals.aspx