排序號碼數字

Question

var a = [[11,"b"], [2,"b"], [11,"a"], [1,"a"], [1,"a"]]; 
a.sort(); 
alert(JSON.stringify(a)); 

給出：

[[1,"a"],[1,"a"],[11,"a"],[11,"b"],[2,"b"]] 

我怎麼樣數值？

Answer 1

假設內部數組的第一個元素將是總是一個數字，你要排序的數組，它立足，你可以比較來自內部陣列第一[0]。

注意：a[0] - b[0]將按升序對元素進行排序。

const a = [[11,"b"], [2,"b"], [11,"a"], [1,"a"], [1,"a"]]; 
 

 
const r = a.slice().sort((a, b) => a[0] - b[0]); 
 

 
console.log(JSON.stringify(r));

Answer 2

可以使用underscoreJs _.sortby功能

var a = [[11,"b"], [2,"b"], [11,"a"], [1,"a"], [1,"a"]]; 
 
var b = _.sortBy(a,function(val){ 
 
    return val[0]; 
 
}); 
 
console.log(JSON.stringify(b));

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