c# - How do I search user input for specific characters?

Question

New to C#, but I love it! I used to use java and still do sometimes, but C# in Visual Studio is amazing.

Now the business...

I want to create a console application that prints messages to the console whenever the user inputs a sentence containing either a T, a t(lower case) or a question mark (?)

I have tried the below, but I have not been successful. It must look like kindergarten scrawl to some of you.

Someone please help me. I thank you in advance!

class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine("Type a sentence without using the letter T or a question mark.");
        Console.ReadLine();
        string userValue;
        userValue = Console.ReadLine();


        if(userValue.Contains("T"))
        {
            Console.WriteLine("Invalid");
        }
        else if(userValue.Contains("t"))
        {
            Console.WriteLine("Invalid");
            Console.ReadLine();
        }
            else if (userValue.Contains("?"));
        {
        Console.WriteLine("Invalid");
        Console.ReadLine();

Answer 1

T、t、または ? を確認したい場合は、これを試してください。

if((userValue.Contains("T") || if(userValue.Contains("t") || (userValue.Contains("?"))
{
    Console.WriteLine(userValue);
}
else
{
    Console.WriteLine("Invalid");
}

Answer 2

疑問符を最後に付ける必要がある場合は、userValue.endWith("?") を使用してみてください。または、入力が疑問符のみかどうかを確認したい場合は、userValue == "?" を試してください。

Answer 3

あなたはこれを行うことができます

if(userValue.Contains("T") ||userValue.Contains("t") ||userValue.Contains("?"))
    {
        Console.WriteLine("Invalid");
        Console.ReadLine();
    }