截取字符串前几位
 
var disName ='开心一族漂亮家园';
var shortName = disName.substring(0,5);
console.log(shortName);//打印结果：开心一族漂
 
 
截取字符串后几位
 
var disName ='开心一族漂亮家园';
var disLength = disName.length;
var shortName = disName.substring(disLength-2,disLength);
console.log(shortName);//打印结果：家园