The example in this article describes the method of using JavaScript to output a square pattern with a specified number of lines. Share it with everyone for your reference. The details are as follows:
Javascript implements the output of a square pattern with a specified number of lines: Click to generate a pattern, and there will be 2 prompt boxes. 1. Enter the characters that make up the pattern. It can only be 1 character. 2. Enter the number of square lines. If it is greater than 10, It will be set to 10 lines
<!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> <div id='zengfang'>此处显示图形</div> <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>
Rendering:
Pattern character: A, number of lines: 5
I hope this article will be helpful to everyone’s JavaScript programming design.