我用PHP中开发了一个以太坊块资源管理器，并成功地与我的服务器Geth节点建立了JSON-RPC通信。然而，当我试图找出最后一个区块时，我陷入了困境。我在https://ethereum.gitbooks.io/frontier-guide/content/rpc.html 中读到了很不错的内容，但是我没有任何方法去查询到以太坊节点的哪一个是最后一个块。一旦我得到了块哈希，我就可以有接口检索完整的信息块，但我不知道如何找到最新的块哈希。
API接口中eth_blockNumber应该返回最新的块号，但是如何得到哈希？
问题解答
user@Kumquat:~$ curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBlockByNumber","params":["latest", false],"id":1}' localhost:8545
{"jsonrpc":"2.0","id":1,"result":{"difficulty":"0x31962a3fc82b",
"extraData":"0x4477617266506f6f6c",
"gasLimit":"0x47c3d8",
"gasUsed":"0x0",
"hash":"0x78bfef68fccd4507f9f4804ba5c65eb2f928ea45b3383ade88aaa720f1209cba",
"logsBloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
"miner":"0x2a65aca4d5fc5b5c859090a6c34d164135398226",
"nonce":"0xa5e8fb780cc2cd5e",
"number":"0x1e655a",
"parentHash":"0x8b535592eb3192017a527bbf8e3596da86b3abea51d6257898b2ced9d3a83826",
"receiptRoot":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421",
"sha3Uncles":"0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347",
"size":"0x20e",
"stateRoot":"0xdc6ed0a382e50edfedb6bd296892690eb97eb3fc88fd55088d5ea753c48253dc",
"timestamp":"0x579f4981",
"totalDifficulty":"0x25cff06a0d96f4bee",
"transactions":[],
"transactionsRoot":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421",
"uncles":[]}}
用latest也可以用eth_blockNumber，来得到最新块。
你可以参考这个以太坊JSON RPC API
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来源：oschina
链接：https://my.oschina.net/u/3837977/blog/1859203