sublime 将tab替换为4个空格 & 显示空格

preferences -> settings -> 在右侧的json中加入(左侧的默认配置是无法修改的，可以在默认配置中搜到这几个配置)

　　// The number of spaces a tab is considered equal to(一个tab相当于多少个空格)
    "tab_size": 4,

    // Set to true to insert spaces when tab is pressed(设置为true表示按下tab键时插入空格符)
    "translate_tabs_to_spaces": true,

    // Set to "none" to turn off drawing white space, "selection" to draw only the
    // white space within the selection, and "all" to draw all white space(设置成"none"将关闭空格绘制，设置成"selection"只在选中的时候绘制空格，设置成"all"任何时候都绘制空格) 
　　"draw_white_space": "all",