Added crowdfund contract

Author: rakeshbs

crowdfund.sol

@@ -0,0 +1,54 @@
+contract CrowdFund {
+  struct Funder {
+    address addr;
+    uint amount;
+  }
+
+  event FundsReceived(address sender);
+  event GoalCrossed();
+
+  mapping (uint => Funder) funders;
+  uint public numberOfFunders = 0;
+  address accountToSendTo;
+  uint public goalAmount;
+  uint public deadline;
+  bool public isOpen = true;
+  uint public amountReceived = 0;
+
+  function CrowdFund(address _accountToSendTo, uint _goalAmount, uint _duration) {
+    accountToSendTo = _accountToSendTo;
+    goalAmount = _goalAmount * 1 ether;
+    deadline = now + _duration * 1 minutes;
+  }
+
+  // This function is called when someone sends money to the contract.
+  function () {
+    uint amount = msg.value;
+    funders[numberOfFunders++] = (Funder({addr: msg.sender, amount: amount}));
+    amountReceived += amount;
+    FundsReceived(msg.sender);
+    if (amountReceived > goalAmount) {
+      GoalCrossed();
+    }
+  }
+
+  // Return the status of the goal and received amount
+  function checkStatus() constant returns (uint goal, uint received) {
+    goal = goalAmount;
+    received = amountReceived;
+  }
+
+  function transfer() {
+    if (now >= deadline) {
+      if (amountReceived >= goalAmount) {
+        accountToSendTo.send(amountReceived);
+      } else {
+        for (uint i = 0; i < numberOfFunders; i++) {
+          Funder funder = funders[i];
+          funder.addr.send(funder.amount);
+        }
+      }
+      isOpen = false;
+    }
+  }
+}