How do I add an integer to a string using Console.WriteLine?-CodePudding

I'm currently writing a program in C# and I'm practicing using integers. I'm trying to make it so the written line comes out with the int at the end. It doesn't give me the outcome I want though, and when I searched on Google it didn't give me the solution I was looking for.

Code:

Random rnd = new Random();
int Pi = rnd.Next(1,5); 

Console.WriteLine("Checking 'Pi' value...");
Console.Beep(37,1000);
Console.WriteLine("Pi value found. Pi = ",Pi);
Console.ReadKey();

Outcome:

Checking 'Pi' value...
Pi value found. Pi =

If you know anything I can try, please let me know.

CodePudding user response：

There are many ways to do this:

// placeholder
Console.WriteLine("Pi value found. Pi = {0}",Pi);

// concatenation
Console.WriteLine("Pi value found. Pi = "   Pi.ToString());

// interpolation
Console.WriteLine($"Pi value found. Pi = {Pi}");

// StringBuilder
var sb = new StringBuilder("Pi value found. Pi = ").Append(Pi);
Console.WriteLine(sb);

// multiple writes
Console.Write("Pi value found. Pi = ");
Console.WriteLine(Pi);

CodePudding user response：

Console.WriteLine("Pi Value found. Pi ="   Pi);

CodePudding user response：

There are multiple ways of doing this.

Console.WriteLine("Pi Value found. Pi = " Pi);, which is a shortened version of Console.WriteLine("Pi Value found. Pi = " Pi.ToString());.

This works because operators like do different things depending on what you use them on. C# automatically adds ToString() to your integer, converting it to, well, a string. This means what you're actually passing into Console.WriteLine now looks like this (assuming your random number generation generated the number 4 in this case: "Pi Value found. Pi = " "4". Notice the quotation marks around the 4 - you now simply have two strings. For two strings, the " "-Operator concatenates them, creating the single string "Pi Value found. Pi = 4" in this case.

Console.WriteLine($"Pi Value found. Pi = {Pi}") or Console.WriteLine("Pi Value found. Pi = {0}", Pi) (although not quite the same technically, they're different ways of writing essentially the same thing for your purposes)

This is string interpolation. Essentially what you're doing with this is defining a template to format the string by - done either directly by the compiler, which is the $-method of doing it (see here for more details), or by providing a template that Console.WriteLine passes into String.Format for you.

It doesn't really matter which of these you choose, they are all valid ways of achieving the same goal.

CodePudding user response：

string.Format(@"The value of Pi is = {0}", pi);