Question

我是每个人，我必须将一个字符转换为keyCode ...我不能转换为charCode ...

例如，如果我有一个＆＃34;。＆＃34; （一个点）我需要获得＆＃34; 190＆＃34;结果..但如果我做

".".charCodeAt(0)

我获得＆＃34; 46＆＃34; ...＆＃34; 46＆＃34;不是我想要的结果...... 我也尝试过做

String.fromCharCode(190);

在这种情况下，我没有获得＆＃34;。＆＃34;但是我得到了＃34; 3/4＆＃34;。

如何将角色转换为＆＃34; 190＆＃34;？

更新我必须将键盘输入与＆＃34;字符串中的值进行比较＆＃34; ...我需要做类似的事情

window.addEventListener('keydown', function(e){
    if(e.keyCode == ".") <-- I need to get the keyCode of the "."
    {
        //Do something
    }
});

这是一个例子....我不知道哪个是我需要比较的字符......它可能是＆＃34;。＆＃34;，或者＆＃34;，＆＃ 34;，o其他东西......

谢谢大家。

Answer 1

我在想，你让我想起了我需要做的一些事情。你可以做的是使用eventListener并将代码记录到控制台。例如：

public class MainActivity extends Activity implements ConnectionCallbacks,
        OnConnectionFailedListener, LocationListener {

    // LogCat tag
    private static final String TAG = MainActivity.class.getSimpleName();

    private final static int PLAY_SERVICES_RESOLUTION_REQUEST = 1000;

    private Location mLastLocation;

    // Google client to interact with Google API
    private GoogleApiClient mGoogleApiClient;

    // boolean flag to toggle periodic location updates
    private boolean mRequestingLocationUpdates = false;

    private LocationRequest mLocationRequest;

    // Location updates intervals in sec
    private static int UPDATE_INTERVAL = 10000; // 10 sec
    private static int FATEST_INTERVAL = 5000; // 5 sec
    private static int DISPLACEMENT = 10; // 10 meters

    // UI elements
    private TextView lblLocation;
    private Button btnShowLocation, btnStartLocationUpdates;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        lblLocation = (TextView) findViewById(R.id.lblLocation);
        btnShowLocation = (Button) findViewById(R.id.btnShowLocation);
        btnStartLocationUpdates = (Button) findViewById(R.id.btnLocationUpdates);

        // First we need to check availability of play services
        if (checkPlayServices()) {

            // Building the GoogleApi client
            buildGoogleApiClient();

            createLocationRequest();
        }

        // Show location button click listener
        btnShowLocation.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                displayLocation();
            }
        });

        // Toggling the periodic location updates
        btnStartLocationUpdates.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                togglePeriodicLocationUpdates();
            }
        });

    }

    @Override
    protected void onStart() {
        super.onStart();
        if (mGoogleApiClient != null) {
            mGoogleApiClient.connect();
        }
    }

    @Override
    protected void onResume() {
        super.onResume();

        checkPlayServices();

        // Resuming the periodic location updates
        if (mGoogleApiClient.isConnected() && mRequestingLocationUpdates) {
            startLocationUpdates();
        }
    }

    @Override
    protected void onStop() {
        super.onStop();
        if (mGoogleApiClient.isConnected()) {
            mGoogleApiClient.disconnect();
        }
    }

    @Override
    protected void onPause() {
        super.onPause();
        stopLocationUpdates();
    }

    /**
     * Method to display the location on UI
     * */
    private void displayLocation() {

        mLastLocation = LocationServices.FusedLocationApi
                .getLastLocation(mGoogleApiClient);

        if (mLastLocation != null) {
            double latitude = mLastLocation.getLatitude();
            double longitude = mLastLocation.getLongitude();

            lblLocation.setText(latitude + ", " + longitude);

        } else {

            lblLocation
                    .setText("(Couldn't get the location. Make sure location is enabled on the device)");
        }
    }

    /**
     * Method to toggle periodic location updates
     * */
    private void togglePeriodicLocationUpdates() {
        if (!mRequestingLocationUpdates) {
            // Changing the button text
            btnStartLocationUpdates
                    .setText(getString(R.string.btn_stop_location_updates));

            mRequestingLocationUpdates = true;

            // Starting the location updates
            startLocationUpdates();

            Log.d(TAG, "Periodic location updates started!");

        } else {
            // Changing the button text
            btnStartLocationUpdates
                    .setText(getString(R.string.btn_start_location_updates));

            mRequestingLocationUpdates = false;

            // Stopping the location updates
            stopLocationUpdates();

            Log.d(TAG, "Periodic location updates stopped!");
        }
    }

    /**
     * Creating google api client object
     * */
    protected synchronized void buildGoogleApiClient() {
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API).build();
    }

    /**
     * Creating location request object
     * */
    protected void createLocationRequest() {
        mLocationRequest = new LocationRequest();
        mLocationRequest.setInterval(UPDATE_INTERVAL);
        mLocationRequest.setFastestInterval(FATEST_INTERVAL);
        mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
        mLocationRequest.setSmallestDisplacement(DISPLACEMENT);
    }

    /**
     * Method to verify google play services on the device
     * */
    private boolean checkPlayServices() {
        int resultCode = GooglePlayServicesUtil
                .isGooglePlayServicesAvailable(this);
        if (resultCode != ConnectionResult.SUCCESS) {
            if (GooglePlayServicesUtil.isUserRecoverableError(resultCode)) {
                GooglePlayServicesUtil.getErrorDialog(resultCode, this,
                        PLAY_SERVICES_RESOLUTION_REQUEST).show();
            } else {
                Toast.makeText(getApplicationContext(),
                        "This device is not supported.", Toast.LENGTH_LONG)
                        .show();
                finish();
            }
            return false;
        }
        return true;
    }

    /**
     * Starting the location updates
     * */
    protected void startLocationUpdates() {

        LocationServices.FusedLocationApi.requestLocationUpdates(
                mGoogleApiClient, mLocationRequest, this);

    }

    /**
     * Stopping location updates
     */
    protected void stopLocationUpdates() {
        LocationServices.FusedLocationApi.removeLocationUpdates(
                mGoogleApiClient, this);
    }

    /**
     * Google api callback methods
     */
    @Override
    public void onConnectionFailed(ConnectionResult result) {
        Log.i(TAG, "Connection failed: ConnectionResult.getErrorCode() = "
                + result.getErrorCode());
    }

    @Override
    public void onConnected(Bundle arg0) {

        // Once connected with google api, get the location
        displayLocation();

        if (mRequestingLocationUpdates) {
            startLocationUpdates();
        }
    }

    @Override
    public void onConnectionSuspended(int arg0) {
        mGoogleApiClient.connect();
    }

    @Override
    public void onLocationChanged(Location location) {
        // Assign the new location
        mLastLocation = location;

        Toast.makeText(getApplicationContext(), "Location changed!",
                Toast.LENGTH_SHORT).show();

        // Displaying the new location on UI
        displayLocation();
    }

}

这将只记录键盘上每个按键的键码

这里是JS小提琴的链接：https://jsfiddle.net/ToreanJoel/09798khL/

Answer 2

虽然我没有将特殊字符转换为keyCodes的解决方案（另请参阅我的答案：https://stackoverflow.com/a/49897083/9219743），这里有另一种解决方案 - 只需使用：

if(e.key == '.') {//do something}

与e.key（实际角色）进行比较，而不是e.keyCode。

从字符转换为KeyCode

2 个答案: