How to check for a specific value in List<T> foreach loop - asp.net

Question

Need help checking for a specific value in List<T> foreach loop. If there is specific value then display a specific string value.
For example how do I…
If (value.something_2 == "Null")
{
value.something_2 == ".";
}
Elseif (value.something_2 == " ")
{
value.something_2 == "0";
}
How would I incorporate the above example within the “foreach” loop?
See code below.
protected void MyReport(string filename, IMyRepository repository)
{
using (FileStream fileStream = new FileStream(Server.MapPath(#"~/Includes/") + filename, FileMode.Create))
{
using (StreamWriter writer = new StreamWriter(fileStream))
{
List<Report> _report = repository.GetMyReport().ToList();
foreach (var value in _report)
{
String row01 = String.Format("{0, -10}{1, 23}{2, 120}{3, 8}",
value.somthing_1,
values.something_2,
value.something_3);
String row02 = String.Format("{0, -10}{1, 23}{2, 120}{3, 8}",
value.somthing_4,
values.something_5,
value.something_6);
Writer.WriteLine(row01);
Writer.WriteLine(row02);
}
}
writer.Close();
}
}

Answer 1

There is no clever built-in String.Format that you can do for this if that's what you have in mind. However, the compiler has some tricks that can reduce the amount of code you need to write e.g.
// if it's null, assign it to "."
var s2 = value.something_2 ?? ".";
// it can never be null here, so if there is whitespace default to "0"
value.something_2 = String.IsNullOrWhitespace(s2) ? "0" : s2;

Answer 2

If I'm understanding what you're saying, it might be easier just to have another function returning the (possibly) modified string and just pass each of your values into it, inline.
Sting row01 = String.Format("{0, -10}{1, 23}{2, 120}{3, 8}", myFunc(value.somthing_1), myFunc(values.something_2), myFunc(value.something_3));
and then have this in the same class
private string myFunc(string something){
if (something == “Null”){
return “.“;
} else if (something == “ “) {
return “0”;
} else {
return something;
}
}