按字符对JavaScript字符中的字符串进行排序

Question

I am trying to sort a list of strings when a character is entered. Suppose I have strings like "Dog", "Ball", "Rabbit", "Pizza" etc. and when "d" is entered by user first "Dog" should come then "Ball", then "Pizza" and finally "Rabbit" should display.

How to achieve this functionality. Any clues please.

Answer 1

I think you can use this code. Its not optimized but you can get the idea

    <script type="text/javascript">
function fnc()
{
    var arr=new Array;
    var arr1=new Array;
    arr[0]="dog";
    arr[1]="pizza";
    arr[2]="doll";
    for(i=0;i<arr.length;++i)
    {arr1[i]=arr[i].length;}

    arr1=arr1.sort();
    alert(arr1);
}
</script>
<input type="button" onclick="fnc()" />

Answer 2

var reg = /^d/i;  //reg exp to check array item first char
['Pizza', 'Dog', 'Ball', 'Foo'].sort(
function(a, b) { 
    if (reg.test(a)) {
        if (reg.test(b)) 
            return a > b; 
        return -1;
    } 
    if (reg.test(b)) { 
        if (reg.test(a)) 
            return a > b;
        return 1; 
    } 
    return a > b; 
})

returns ["Dog", "Ball", "Foo", "Pizza"]

Answer 3

Generate a sort function depending on the current input.
If the current input matches one item in sort, default it first. If it matches both or none do a normal string compare.

function generateSortFunction(str){
    var s = str.toLowerCase(), sl = s.length; // save re-computation
    return function sort(a,b){
        var am = +( a.length >= sl && a.slice(0, sl).toLowerCase() === s ),
            bm = +( b.length >= sl && b.slice(0, sl).toLowerCase() === s );
        if( am ^ bm ) return bm - am; // XOR then -1 if a first, 1 if b first.
        return a.localeCompare(b); // else sort normally
    };
}

// Using it
["Dog", "Ball", "Rabbit", "Pizza"].sort( generateSortFunction('d') );
// results in ["Dog", "Ball", "Pizza", "Rabbit"]

Above code uses input as 'd' , modify as required.