java - 使用用户输入访问元素数组

Question

我是 Java 的新手，我正在尝试让用户可以从他们要求的数组中获取什么元素。

int[] aksesArray = {30, 50, 10, 90, 70}; 

因此，如果用户输入答案0，他将获得访问元素0，即30，依此类推。每当用户输入 0, 1, 2, 3, 4 时，答案总是指 30。

我认为问题出在我的 a = aksesArray.length;

import javax.swing.JOptionPane; 

public class pickingArray {


public static void main(String[] args) {

int[] aksesArray = {30, 50, 10, 90, 70};

int inputElm = Integer.parseInt(JOptionPane.showInputDialog("Input Number to find an Element "));
int a = (inputElm);

a = aksesArray.length;


    if ( a == aksesArray.length ) {
        JOptionPane.showMessageDialog(null, "Element you are looking for : " + aksesArray[0] );
    }
    else if ( a == aksesArray[1] ) {
        JOptionPane.showMessageDialog(null, "Element you are looking for : " + aksesArray[1] );
    }
    else if ( a == aksesArray.length ) { 
        JOptionPane.showMessageDialog(null, "Element you are looking for : " + aksesArray[2] );
    }
    else if ( a == aksesArray.length ) { 
        JOptionPane.showMessageDialog(null, "Element you are looking for : " + aksesArray[3] );
    }
    else if ( a == aksesArray.length ) { 
        JOptionPane.showMessageDialog(null, "Element you are looking for : " + aksesArray[4] );
    }
    else {
        JOptionPane.showMessageDialog(null, "No Element " );
    }


    }

}

Answer 1

您可以通过检查输入的数字是否在 aksesArray 的范围内来大大简化您的代码。无论哪种情况，您都可以打印相应的消息。

public static void main(String[] args) {
    int[] aksesArray = {30, 50, 10, 90, 70};

    int inputElm = Integer.parseInt(JOptionPane.showInputDialog("Input Number to find an Element "));

    if (inputElm >= 0 && inputElm < aksesArray.length) {
        JOptionPane.showMessageDialog(null, "Element you are looking for : " + aksesArray[inputElm] );
    }
    else {
        JOptionPane.showMessageDialog(null, "No Element " );
    }
}