How can i convert from ArrayList<String> to double[]?
本问题已经有最佳答案，请猛点这里访问。
我有一个这样的阵列列表：
1 | [5, 181, 138, 95, 136, 179] |
我想做的是将这个列表转换为double[]。像这样。
1 | double[] Fails = new double[]{5, 181, 138, 95, 136, 179}; |
这是我的代码：
1 2 3 4 5 6 7 8 9 10 | ArrayList<String> DatesList = new ArrayList<String>(); ArrayList<String> FailList = new ArrayList<String>(); while (rs2.next()) { DatesList.add(rs2.getString("Date")); FailList.add(rs2.getString("fail")); } double[] Fails = new double[]{FailList}; //obviously it doesn't work.. |
有没有办法把arraylist转换成double[]？
1 2 3 4 5 6 7 8 9 10 11 | List<String> failList = new ArrayList<>(); while (rs2.next()) { //whatever that is (copied from OP) failList.add(rs2.getString("fail")); } double[] failsArray = new double[failList.size()]; //create an array with the size of the failList for (int i = 0; i < failList.size(); ++i) { //iterate over the elements of the list failsArray[i] = Double.parseDouble(failList.get(i)); //store each element as a double in the array } |
这段代码的作用是，它首先创建一个数组