Diagonal win checks in Connect 4 [duplicate]

This question already has an answer here:

Connect 4 check for a win algorithm 5 answers

I am developing a Connect 4 game with 7x7 fields, horizontal and vertical checks but I dont get diagonal checks works

I can win as long as one of the tokens is not in the last column.

This are all checks:

private static int getWinningInDiagonals() {

    // Top-Left -> Bottom-Right
    for (int column = 0; column < 7; column++) {
        int count = 0;
        for (int row = 0; row < 7; row++) {
            if (field[row][column] != 0 && field[row+1][column + row - 1] == field[row][column])
                count++;
            else
                count = 1;
            if (count >= 4) {
                return field[row][column];
            }                   
        }
    }
    // Top-Right -> Bottom-Left
    for (int column = 0; column < 7; column++) {
        int count = 0;
        for (int row = 0; row < 7; row++) {
            if (field[row][column] != 0 && field[row+1][column - row + 1] == field[row][column])
                count++;
            else
                count = 1;
            if (count >= 4) {
                return field[row][column];
            }
        }
    }        
    return 0;
}

For one you want to move down and right at the same time every time, you also only need to go to 3, 3 as a diagonal cannot occur any farther than that without it leaving the bounds of the array.

This should work for your top left to bottom rights if I'm right in assuming that your top left is your 0,0. Doing top right to bottom left is a matter of changing the column and row loops and changing how the offset works.

// Top-Left -> Bottom-Right
for (int column = 0; column < 4; column++) {
    for (int row = 0; row < 4; row++) {
        player = 0;
        if (field[row][column] != 0){
            player=field[row][column];
            offset = 1;
        }
        while (player != 0){
            if (field[row + offset][column + offset] == player){
                offset += 1;
            }else{
                player = 0;
            }
        }                   
        if(offset >= 4){
            return field[row][column];
        }
    }
}