2
我有以下的JavaScript數組:在陣列總結出重複的項目
var President = new Array();
President[0]="Thomas Jefferson";
President[1]="Thomas Jefferson";
President[2]="Thomas Jefferson";
President[3]="Thomas Jefferson";
President[4]="Thomas Jefferson";
President[5]="Thomas Jefferson";
President[6]="Thomas Jefferson";
President[7]="Thomas Jefferson";
President[8]="Thomas Jefferson";
President[9]="Thomas Jefferson";
President[10]="Thomas Jefferson";
President[11]="Thomas Jefferson";
President[12]="Thomas Jefferson";
President[13]="James Madison";
President[14]="James Madison";
President[15]="James Madison";
President[16]="James Madison";
President[17]="James Madison";
President[18]="James Madison";
President[19]="James Madison";
President[20]="Abraham Lincoln";
President[21]="Abraham Lincoln";
President[22]="Abraham Lincoln";
President[23]="Abraham Lincoln";
President[24]="Abraham Lincoln";
President[25]="George Washington";
我如何從中總結出重複的項目,以便輸出如下:
Thomas Jefferson: 13
James Madison: 7
Abraham Lincoln: 5
George Washington: 1
感謝您的幫助!
僅供參考,在發佈問題時,在文本編輯器中有一個「代碼示例」格式按鈕。另外,你到目前爲止嘗試過什麼? –
可能重複的[計數JavaScript數組元素](http://stackoverflow.com/questions/5667888/counting-occurences-of-javascript-array-elements) – j08691