如何将逗号分隔的字符串转换为 Java 中的二维数组？

Question

For example I have some comma separated strings "aron, IA52, 20" "john, IA61, 23" "kleo, IA32, 42" How can I convert them to a 2 dimensional array in the easiest way possible?

Answer 1

As already pointed out in comments, you should use split() while iterating over your comma separated string list and populate your array accordingly. Here is sample code to give you some idea:

List<String> input = Arrays.asList("aron, IA52, 20", "john, IA61, 23", "kleo, IA32, 42");
String[][] array = new String[3][3];
int row = 0;

// Loop Over Comma Separated List and split each string to populate 2D array
for (String commaSeparatedStr : input) {
    String[] parts = commaSeparatedStr.split(",");
    System.arraycopy(parts, 0, array[row], 0, parts.length);
    row++;
}

// Print array
for (int i = 0; i < 3; i++) {
    for (int j = 0; j < 3; j++)
        System.out.print(array[i][j]);
    System.out.println();
}

This prints:

aron IA52 20
john IA61 23
kleo IA32 42

Answer 2

The provided function will parse the string to the 2D matrix. Below is the format of the string that you need to provide to this function.

1.2,2.3,3.5\n3.1,4.70,5.0

function

public double[][] parseStingToArray(String str) {
        System.out.println(str);
        String arr1[] = str.split("\n");

        double[][] ans = new double[arr1.length][];

        for (int i = 0; i < arr1.length; i++) {
            String[] col = arr1[i].split(",");
            ans[i] = new double[col.length];
            for (int j = 0; j < col.length; j++) {
                ans[i][j] = Double.parseDouble(col[j]);
            }
        }

        doubleArray = ans;
        return ans;
    }