小编ser*_*aev的帖子

I am wondering if this is a correct way to create PrivateKey object in Java from HEX string from this website: https://kjur.github.io/jsrsasign/sample/sample-ecdsa.html

Create a BigInteger from a HEX String:

BigInteger priv = new BigInteger(privateKeyFromSite, 16);

And pass to this method:

import java.math.BigInteger;
import java.security.KeyFactory;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.spec.InvalidKeySpecException;

import org.bouncycastle.jce.ECNamedCurveTable;
import org.bouncycastle.jce.spec.ECParameterSpec;
import org.bouncycastle.jce.spec.ECPrivateKeySpec;


public static PrivateKey getPrivateKeyFromECBigIntAndCurve(BigInteger s, String curveName) {

    ECParameterSpec ecParameterSpec = ECNamedCurveTable.getParameterSpec(curveName);

    ECPrivateKeySpec privateKeySpec = new ECPrivateKeySpec(s, ecParameterSpec);
    try {
        KeyFactory keyFactory = KeyFactory.getInstance(EC); …

据我所知,C中的联合一次只能保存1个值,我真的不明白C中的代码是如何理解的,因为event.window不能与event.type同时填充？

while(SDL_PollEvent(&event)) {
switch(event.type)
{
case SDL_WINDOWEVENT:
    switch(event.window.event)

该事件定义为:

typedef union SDL_Event
{
    Uint32 type;                    /**< Event type, shared with all events */
    SDL_CommonEvent common;         /**< Common event data */
    SDL_WindowEvent window;         /**< Window event data */
    SDL_KeyboardEvent key;          /**< Keyboard event data */
    SDL_TextEditingEvent edit;      /**< Text editing event data */
    SDL_TextInputEvent text;        /**< Text input event data */
    SDL_MouseMotionEvent motion;    /**< Mouse motion event data */
    SDL_MouseButtonEvent button;    /**< Mouse button event …