Create contract in Go-ethereum with Solidity, "Hello world" program

Question

I want to create contract in go-ethereum using Solidity, I started with "Hello world" program.

I create a private network:

$geth --genesis private.json --networkid 1234 --datadir /home/user/Documents/genesisdata  console

In here, I make a new account then I coded follow link https://www.ethereum.org/greeter.

var greeterSource ='contract mortal { address owner; function mortal() { owner = msg.sender; } function kill() { if (msg.sender == owner) selfdestruct(owner); } } contract greeter is mortal { string greeting; function greeter(string _greeting) public { greeting = _greeting; } function greet() returns (string) { return greeting; } function test() returns (string){ return greeting; } }'

And I got: undefined

When I code without var like this:

greeterSource ='contract mortal { address owner; function mortal() { owner = msg.sender; } function kill() { if (msg.sender == owner) selfdestruct(owner); } } contract greeter is mortal { string greeting; function greeter(string _greeting) public { greeting = _greeting; } function greet() returns (string) { return greeting; } function test() returns (string){ return greeting; } }'

I got:

"contract mortal { address owner; function mortal() { owner = msg.sender; } function kill() { if (msg.sender == owner) selfdestruct(owner); } } contract greeter is mortal { string greeting; function greeter(string _greeting) public { greeting = _greeting; } function greet() returns (string) { return greeting; } function test() returns (string){ return greeting; } }"

So I continute code without var, I compile:

greeter = greeterContract.new(_greeting,{from:web3.eth.accounts[0], data: greeterCompiled.greeter.code, gas: 210000}, function(e, contract){
if(!e) {

  if(!contract.address) {
    console.log("Contract transaction send: TransactionHash: " + contract.transactionHash + " waiting to be mined...");

  } else {
    console.log("Contract mined! Address: " + contract.address);
    console.log(contract);
  }

}
else{
console.log("Error:>>>>>>>>>>>>>");
console.log(e);
}

})

untill:

greeter.greet();

TypeError: 'greet' is not a function at :1:1

I don't know, how to solve it.

Please show me the problem that I make in this process.

Thanks.

Answer 1

It does not seem that you compiled the source? You just declared a variable holding the source code. That's the main problem.

Also, apparently, your function greet() is not declared with the keyword constant. You'll therefore have to call it with greeter.greet.call()

PS : no need to do this complicated stuff to create your development chain. Just run get --dev --mine --minerthreads 1

Answer 2

var greeterSource=... is correct and Javascript throws this undefined at you every time. Just ignore it.
You can see that the variable was set correctly by typing greeterSource again. You need to compile your contract with solc in order to use it, as the tutoral shows.