如何根据多个条件对数组进行排序？

function sortByMultipleConditions(arr) {
  arr.sort(function(a, b) {
    // 比较条件1
    if (a.condition1 !== b.condition1) {
      return a.condition1 - b.condition1;
    }
    
    // 比较条件2
    if (a.condition2 !== b.condition2) {
      return a.condition2.localeCompare(b.condition2);
    }
    
    // 比较条件3
    if (a.condition3 !== b.condition3) {
      return a.condition3 - b.condition3;
    }
    
    // 如果所有条件都相同，则保持原有顺序
    return 0;
  });
}

// 示例用法
var myArray = [
  { name: 'John', age: 25, score: 80 },
  { name: 'Jane', age: 30, score: 90 },
  { name: 'Bob', age: 20, score: 70 },
  { name: 'Alice', age: 25, score: 85 }
];

sortByMultipleConditions(myArray);

console.log(myArray);