模板字符串用途

1. 取变量

      var name = "liyang";
      var age = 23;
      console.log(`I am ${name},I ${age} years old`)
   

   

    如果想用到反引号，用斜杠转义
      var name = "liyang";
      var age = 23;
      console.log(`I \`\`am ${name},I ${age} years old`)
   

   

2. 展示多行字符串

      $('#root').html(`
          <ul>
              <li>一</li>
              <li>二</li>
              <li>三</li>
          </ul>
      `)