Question

I have a controller action where I validate if any value is entered in fields or not. Here is how I do it:

[HttpPost]
        public ActionResult ValidateFields(string Desc, string Status, string Name )
        {
            string[] fields = new string[3];

            if (string.IsNullOrEmpty(Desc))
                fields[0] = "#Desc";

            if (string.IsNullOrEmpty(Status))
                fields[1] = "#Status";

            if (string.IsNullOrEmpty(Name))
                fields[2] = "#Name ";

// Check if the initialized array "fields" has any items in it.
            if (fields != null)
            { return content("Please enter valid values for " + fields); }

            return content("Validation Successful");
        }

Here array “fields” is initialized and hence its length is never 0. Also, checking for null does not work. All I can do i loop through the array and check if it has any items in it.

Is there a better way of checking if an array has any items in it or just null values?

Also, if there is any better way of validating fields than how I am doing, please let me know.
I want it to be maintainable, if tomorrow I add new fields I want to spend as little time I can to validating them.

Answer 1

Use lists.

    [HttpPost]
    public ActionResult ValidateFields(string Desc, string Status, string Name )
    {
        List<string> fields = new List<string>();

        if (string.IsNullOrEmpty(Desc))
            fields.Add("#Desc");

        if (string.IsNullOrEmpty(Status))
            fields.Add("#Status");

        if (string.IsNullOrEmpty(Name))
            fields.Add("#Name");

        // Check if the list "fields" has any items in it.
        if (fields.Any()) {
             return content("Please enter valid values for " + string.Join(", ", fields)); 
        }

        return content("Validation Successful");
    }

UPDATE

Another, probably better and more maintainable, way to validate is to create a model class, and add validation attributes. See here.