今日分享小知识 document.write会不会覆盖页面内容 先看看示例代码,再看 write 的介绍 01 示例代码 首先,直接来看看下面的示例,判断 document.write 是否会覆盖页面上的内容 示例一:
在此之后,任何一个对当前页面进行操作的document.write()方法将打开—个新的输出流,它将清除当前页面内容(包括源文档的任何变量或值)。 因此,假如希望用脚本生成的HTML替换当前页面,就必须把HTML内容连接起来赋给一个变量,使用一个document.write()方法完成写操作。 不必清除文档并打开一个新数据流,一个document.write()调用就可完成所有的操作。 在延时脚本的最后一个document.write()方法后面,必须确保含有document.close()方法,不这样做就不能显示图像和表单。 并且,任何后面调用的document.write()方法只会把内容追加到页面后,而不会清除现有内容来写入新值。
("当前的时间:"+date+"
");
12 document.write(date.getFullYear()+"年");
13 document.write document.write(date.getHours()+":");
16 document.write(date.getMinutes()+":");
17 document.write document.write("var arr2 = new Array(5)"+"
");
15 document.write("3:创建数组并初始化参数" var arr4=[];
21 document.write("var arr4 = []"+"
");
22 document.write("5:使用括号[ 57 document.write("删除后的效果:"+arr+"
");
58 document.write("
('6.3》》'+Math.ceil(6.3)+'
');
document.write('5》》'+Math.ceil(5)+'
');
document.write( '3.5》》'+Math.ceil(3.5)+'
');
document.write('-5.1》》'+Math.ceil(-5.1)+'
');
document.write ('6.3》》'+Math.floor(6.3)+'
');
document.write('5》》'+Math.floor(5)+'
');
document.write ('6.3》》'+Math.round(6.3)+'
');
document.write('5》》'+Math.round(5)+'
');
document.write document.write('-5.9》》'+Math.round(-5.9)+'
');
document.write('-5.5》》'+Math.round(-5.5)
("圆心的x坐标值是:", circle.x, "
");
document.write("圆心的y坐标值是:", circle.y, "
");
document.write ("姓名:" + st1.name + "
");
document.write("语文:" + st1.chinese + "
");
document.write ("姓名:" + st1.name + "
");
document.write("语文:" + st1.chinese + "
");
document.write ("姓名:", st1.name, "
");
document.write("语文:", st1.chinese, "
");
document.write ("数学:", st1.math, "
");
document.write("英语:", st1.english, "
");
document.write
(flag + "
"); document.write(! = NaN; document.write(!! num1 + "
"); document.write(!!num2 + "
"); document.write(!! document.write(!! obj2 + "
"); document.write("
("第"+(i+1)+"个元素:
");
document.write($spans[i].innerHTML+"
")
}
document.write ("第"+(j+1)+"个元素:
");
document.write($spans1[j].innerHTML+"
");
}
</script>
</html for (var j = 0; j < $spans2.length; j++) {
document.write("第"+(j+1)+"个元素:
");
document.write ("第"+(k+1)+"个元素:
");
document.write($spans3[k].innerHTML+"
");
}
</script>
</html last");
document.write($div2.text()+"
");
//3、非元素选择器
document.write("======非元素选择器====
();
document.write("v=" + v);
document.write("
");
var v2 = getValue; //相当于 v2对象的toString()
document.write("
");
document.write("v2=" + v2()); //调用v2这个函数对象-- ("arr["+x+"]="+ arr[x]+" ");
}
document.write("
");
document.write(" ("数组最大值的下标:"+v);
document.write("
");
document.write("数组最大值:"+v);
document.write("<br ("
document.write(parseInt("10") + " "); document.write(parseInt("10.33") + " "); document.write(parseInt ("34 45 66") + " "); document.write(parseInt(" 60 ") + " "); document.write(parseInt("40 years") + " "); document.write(parseInt("He was 40") + " "); document.write(" "); document.write(parseInt("10",10 )+ " "); document.write(parseInt("010")+ " "); document.write(parseInt("10",8)+ " "); document.write( parseInt("0x10")+ " "); document.write(parseInt("10",16)+ " "); 2、使用“~~小数值”语句。
//取绝对值 document.write(Math.abs(-2)); //四舍五入 document.write(Math.round(5.5)); //返回最高值 document.write(Math.max(5,7)); //返回最低值 document.write(Math.round(5.7)); //返回两个数的次幂 document.write(Math.pow(5.7)); //返回平方根 document.write(sqrt.round(5)); 字符串函数: var str="hello document.write(str.charAt(0)); //返回字符在字符串中最后一次出现的位置 document.write(str.lastIndexOf(s)); / /截取字符串 document.write(str.substring(1,3)); //截取字符串相应的长度 document.write(str.substr(1,3));
2 document.write('hello world
');
3 document.write('第'+i+'列、'+'
');
4 }
5 document.write 用字符串引进来
循环输出0-100
1 for(var a=0; a<=100; a++){
2 document.write(a+'
')
3 }
4 document.write( 6 }
7 document.write('');
8 }
9 document.write('');
10 document.write('<hr color }
7 document.write('');
8 }
9 document.write('');
更改,原理不变调数据——变化1
1 document.write( '='+(x*y)+'');
7 }
8 document.write('');
9 }
10 document.write('');
11 document.write
document.write("
"+x);
var x="5"+"5";
document.write("
"+x);
var x=5;
document.write case 0:
document.write("0");
break;
default:
document.write("Nothing");
}
document.write >");
document.write(str.toLowerCase()+"
");
document.write(str.replace("!" ");
document.write(b);
//math
document.write("
"+Math.random());
document.write("
"+Math.round ;
document.write("
"+re.test("expression"));
document.write("
"+re.exec("Hello world!
(arr)
document.write("
")
document.write(arr.pop())
document.write("
")
document.write( (arr + "
")
document.write(arr.push("James") + "
")
document.write(arr)
</script>
输出:
George (arr + "
")
document.write(arr.shift() + "
")
document.write(arr)
</script>
输出:
George,John (arr + "
")
document.write(arr.slice(1) + "
")
document.write(arr)
</script>
输出:
George,John (arr + "
")
document.write(arr.slice(2,4) + "
")
document.write(arr)
</script>
输出:
George,
("浮点数1:"+num1+"
")
document.write("浮点数2:"+num2+"
")
document.write("浮点数3:"+num3+"
")
document.write
"
document.write(mystring)
document.write(mystring.bold())
document.write(mystring.toUpperCase
"
document.write(str1)
document.write(str1.substring(0,13)+"
")
document.write(str1.substr
"
document.write(str1+"
")
document.write(str2)
document.write(str1.concat(str2))
document.write
"
document.write(str1)
document.write(str1.big())
document.write(str1.small())
document.write
: Apple document.write(fruits[1]); // Prints: Banana document.write(fruits[2]); // Prints: Mango document.write (colors); // Prints: Green,Blue document.write(removed); // Prints: Red (one item array) document.write : Red,Green,Blue document.write(colors.join("")); // Prints: RedGreenBlue document.write(colors.join( ")); // Prints: 0 document.write(fruits.indexOf("Banana")); // Prints: 1 document.write(fruits.indexOf document.write(arr.includes(6)); // Prints: false document.write(arr.includes(1, 2)); // Prints: true
+ "
");
var y = '';
document.write(typeof(y) + "
");
var b = true;
document.write == 11) {
document.write("男性");
} else {
document.write("女性");
}
</script>
("星期一");break;
case 2:document.write("星期二");break;
case 3:document.write("星期三");break ;
case 4:document.write("星期四");break;
case 5:document.write("星期五");break;
case 6:document.write("星期六");break;
case 7:document.write("星期七");break;
default:document.write
i % 100 === 0) {
document.write("
")
}
};
console.timeEnd('second');
document.write [i++];) {
document.write(len.nummber + 1)
if (i % 100 === 0) {
document.write("
") ((resp, index) => {
document.write(resp.nummber + 1)
if (index % 100 === 0) {
document.write ("开始时间:"+start)
document.write("
")
func();
var end = new Date().getTime();
document.write ("结束时间:"+end)
document.write("
")
analysis_data.push(end - start)
document.write("用时:" +
("姓名:张平");
document.write("
性别:男");
document.write("
年龄:36"); document.write("
职业:教师");
document.write("
爱好:足球");
}
</script>
</head> ");
document.write(" 年龄:", nl, "    ");
document.write(" for (i in x) {
document.write(x[i], "  ")
}
document.write("
" :", y, "
");
document.write("数组的值为:");
for (i in x) {
document.write(x
(num); document.write(a); document.write("
(num+"---"+typeof(num) +"
");
document.write(num2+"---"+typeof(num2) +"
");
document.write document.write((3>4)+"
"); //fasle document.write(("abc" < "bcd") + "
");//true document.write(("123" == 123) + "
");//true document.write(("123" === 123) + "
");//fasle (arr1+"
");
document.write(arr2+"
");
document.write(arr3+"
");
document.write (arr+"
");
document.write(arr[0]+"
");
document.write(arr[1]+"
");
document.write