c# - C# XNA 游戏中的文本框

Question

我是 XNA 新手。我正在制作一款需要关卡编辑器的游戏。我需要一个文本框来获取关卡名称及其描述。所以我写了这样的代码:

if (isSaveBox)
        {
            KeyboardState ks = Keyboard.GetState();
            Keys[] keys = ks.GetPressedKeys();
            Keys tempKey = Keys.None;

            foreach (Keys key in keys)
            {
                Keys currentKey = key;
                if (ks.IsKeyUp(lastKey))
                {
                    string toadd = key.ToString();
                    if (!(key == Keys.None) && key != Keys.Space && key != Keys.Back && key != Keys.Enter)
                    {
                        levelName += toadd;
                    }
                    else if (key == Keys.Space)
                    {
                        levelName += " ";
                    }
                    else if (key == Keys.Back)
                    {
                        levelName.Remove(levelName.Length - 1);
                        lastKey = currentKey;
                    }
                }
                if (currentKey != Keys.None && ks.IsKeyDown(currentKey))
                {
                    tempKey = currentKey;
                }
            }

            lastKey = tempKey;
            message = "Save level" + "\n" + "Enter - yes / Esc - no" + "\n" + levelName;

但是当我尝试输入一些字母时，它们不会被添加到 levelName 字符串中。有人可以帮我解决这个问题吗？

Answer 1

据我所知，您的代码运行良好。我玩弄它并添加了一些改进。你不需要一些东西，而我做到了，所以当你按住一个键时，它不会那么快地发送垃圾邮件。我本来可以添加对符号和大写字母等其他键的支持，但它是一个很长的 switch 语句，所以你可以看看 this文章并轻松实现。

我添加了更多变量，所有与文本框相关的内容现在都应该读作

    Keys[] lastKeys;
    KeyboardState lastKeyboardState;

    public double timer;

    public string levelName;

如果需要，您还可以将 currentKeyboardState 变量添加为全局变量。

现在对于代码，我将它分成 2 个方法以避免必须复制代码两次

if (isSaveBox)
{
    //Get the current keyboard state and keys that are pressed
    KeyboardState keyboardState = Keyboard.GetState();
    Keys[] keys = keyboardState.GetPressedKeys();

    foreach (Keys currentKey in keys)
    {
        if (currentKey != Keys.None)
        {
            //If we have pressed the same key twice, wait atleast 125ms before adding it again
            if (lastKeys.Contains(currentKey))
            {
                if ((gameTime.TotalGameTime.TotalMilliseconds - timer > 125))
                    HandleKey(gameTime, currentKey);
            }
            //If we press a new key, add it
            else if (!lastKeys.Contains(currentKey))
                HandleKey(gameTime, currentKey);
        }
    }

    //Save the last keys and pressed keys array
    lastKeyboardState = keyboardState;
    lastKeys = keys;
}

以及重置计时器和实际计算字符串的方法(这是您要添加移位和符号等代码的地方)

private void HandleKey(GameTime gameTime, Keys currentKey)
{
    string keyString = currentKey.ToString();
    if (currentKey == Keys.Space)
        levelName += " ";
    else if ((currentKey == Keys.Back || currentKey == Keys.Delete) && levelName.Length > 0)
        levelName = levelName.Remove(levelName.Length - 1);
    else if (currentKey == Keys.Enter)
        return;
    else
        levelName += keyString;
    //Set the timer to the current time
    timer = gameTime.TotalGameTime.TotalMilliseconds;
}

您还可以使用 StringBuilder 进行进一步优化。

如果您想继续编写自己的 UI，请继续。我仍然会推荐使用 UI 库(我使用新恢复的 Neoforce Controls )但是关于 here 的讨论更大。 .