How to implement the effect of javascript outputting a square pattern with a specified number of lines-JS Tutorial-php.cn

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How to implement the effect of javascript outputting a square pattern with a specified number of lines

巴扎黑

Sep 06, 2017 am 10:06 AM

javascriptjsNumber of lines

本文实例讲述了javascript实现输出指定行数正方形图案的方法。分享给大家供大家参考。具体如下：

javascript实现输出指定行数的正方形图案：点击生成图案，会有2个提示框，1，输入图案的组成字符，只能是1个字符哦2，输入正方形行数，路过大于10，会设置为10行数

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title> 生成正方形 </title>
<Script type="text/javascript">
//动态测字符的宽度，传入字符，放在span，判断宽度变化，返回
function get_width(zifu){
if(cwidth.innerHTML.length>0)cwidth.innerHTML="";//路过有元素，清空
var oldwidth=cwidth.offsetWidth;
cwidth.innerHTML=zifu;
var zifu_width=cwidth.offsetWidth-oldwidth;
cwidth.innerHTML="";
//alert(zifu_width);
return zifu_width;
}
//输出正方形函数
function create(){
var tuxing=prompt("请输入图案，必须1个字符");//图案，路 a 
if(tuxing==null||tuxing==""||tuxing.length>1){
alert("请输入图 案,图案必须1个字符");
return false;
}
//提示框，输入行数
var count=prompt("请输入正方形的行数");
if(count==null||count==""||count<1||isNaN(count)){
alert("您的输入的行数存在问题，1.不得空2.大于1 3.不得为非数字");
return false;
}
//根据行数，得到一行的字符窜
if(count>10){count=10;alert("输入的行数大于10，自动修改为10");}
var hangstr="";
for(i=1;i<=count;i++){
hangstr+=tuxing+" ";
//判断变长是否超过文档的
if(get_width(hangstr)>maxw-100){
alert("过长的行");
count=i-1;
hangstr=oldhangstr;
break;
}
oldhangstr=hangstr;
}
//生成图形字符串
var tustr="";//图形字符串
for(i=1;i<=count;i++)tustr+=hangstr+"<br/>";
//把图形字符串放入图形层
zengfang.innerHTML=tustr;
}
</script>
 </head>
 <body>
 <p id="zengfang">此处显示图形</p>
 <input type="button" value="生成正方形图案" onclick="create()">
<br>
<span id="cwidth"></span>
<!-- 测试获取字符串的宽度，因为行数过大，会超过文档范围，而发生折行
<input type="text" value="" id="text1">
 <input type="button" value="显示字符宽度" onclick="get_width(text1.value)">
 -->
 <Script type="text/javascript">
 var maxh=document.body.clientHeight;//文档高 正方形最大长度
 var maxw=document.body.clientWidth;//文档宽，正方形最大长度
 //alert(maxh);
 //alert(maxw);
 </script>
 </body>
</html>

效果图：

图案字符：A，行数：5

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