在C＃类中使用通用方法

Question

Here is my current code:

namespace WindowsFormsApp1
{
public partial class Form1 : Form 
{
    public Random random = new Random();
    public int[] randomInt = new int[20];
    public double[] randomDouble = new double[20];

    public string searchKey;
    public int intOrDouble; // 0 if int, 1 if double

    public static int Search<T>(T[] inputArray, T key) where T : IComparable<T>
    {
        for (int i = 0; i < 20; i++)
        {
            if (inputArray[i].CompareTo(key) == 0)
            {
                return i;
            }
        }
        return -1;
    }

    public Form1()
    {
        InitializeComponent();
    }

    private void randomIntGeneration_Click(object sender, EventArgs e)
    {
        randomNumbersTextBox.Clear(); // empty the textbox
        intOrDouble = 0; // this is for knowing which parameter to send to search method

        // generate 20 random integers and display them in the textbox
        for (int i = 0; i < 20; ++i)
        {
            randomInt[i] = random.Next(0, 100);
            randomNumbersTextBox.Text += randomInt[i].ToString() + "   ";
        }
    }

    private void randomDoubleGenerator_Click(object sender, EventArgs e)
    {
        randomNumbersTextBox.Clear(); // empty the textbox
        intOrDouble = 1; // this is for knowing which parameter to send to search method

        // generate 20 random doubles and display them in the textbox
        for (int i = 0; i < 20; ++i)
        {
            randomDouble[i] = random.NextDouble() + random.Next(0, 100);
            randomNumbersTextBox.Text += randomDouble[i].ToString() + "   ";
        }
    }

    private void searchArrayButton_Click(object sender, EventArgs e)
    {
        searchKey = searchKeyTextBox.Text;
        if(intOrDouble == 0) // int array passed
        {
            resultsTextBox.Text = Search(randomInt, searchKey).ToString();
        }
        else
        {
            resultsTextBox.Text = Search(randomDouble, searchKey).ToString();
        }
    }
}

}

What i am trying to do is use this generic method. The GUI allows the user to generate a random array of either ints or doubles. I then want to use the Search method in the searchArrayButton_Click control to display whether or not the "searchKey" value entered is in the array. The error I am getting is "The type arguments for method 'Form1.Search(T[], T)' cannot be inferred from the usage. Try specifying the type arguments explicitly." They appear toward the bottom of the code when I try to call Search twice in the searchArrayButton_Click control.

Answer 1

You're trying to search an array of int or double values for a string . As a result, your call to Search has two arguments with two different types. That doesn't match the function signature.

You need to convert whatever is in that textbox into the value you are searching for, either an int or a double.

if(intOrDouble == 0) // int array passed
{
    resultsTextBox.Text = Search(randomInt, int.Parse(searchKey)).ToString();
}
else
{
    resultsTextBox.Text = Search(randomDouble, double.Parse(searchKey)).ToString();
}