Is it possible to have a variable with a string format that you would like interpolated.
public class Setting
{
public string Format { get; set; }
}
var setting = new Setting { Format = "The car is {colour}" };
var colour = "black";
var output = $"{setting.Format}";
Expected output
"The car is black".
You can't do that. String interpolation is a purely compile-time feature.
No you can't do that, but you can achieve the same with a slightly different approach, that I've come to like:
public class Setting
{
public Func<string, string> Format { get; set; }
}
then you can pass your string argument to Format:
var setting = new Setting { Format = s => $"The car is {s}" };
var output = setting.Format("black");
Setting { Format = s => string.Format("The car is {0}", s) };Why not?
First of all, you can't use a local variable before declaring it in C#. So
First declare the colour before using it. Then "interpolate" the string assigned to Format and you are done.
var colour = "black";
var setting = new Setting { Format = $"The car is {colour}" };
var output = $"{setting.Format}";
Console.WriteLine(output);
Output:
The car is black.
You can do a slight alteration on it, like the following:
public class Setting
{
public string Format
{
get
{
return String.Format(this.Format, this.Colour);
}
set
{
Format = value;
}
}
public string Colour { get; set; }
}
var setting = new Setting { Format = "The car is {0}", Colour = "black" };
Then the output will be "The car is black".
I haven't tested this code.
string.Format. if you have variables and not constants. and you can't have your cake and eat it too.FormatWithor a similar. Be warned that every one of these custom functions has slightly different behavior. See also Named Formats Redux.