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PHP验证码图片展示不了

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Jun 13, 2016 pm 12:52 PM

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PHP验证码图片显示不了
PHP验证码图片显示不了，显示的是一个红色的叉叉。代码如下：

image.php

<br />
<?php<br />
	session_start();<br />
	if(isset($_POST['submit'])){<br />
		if(trim($_POST["test"])==$_SESSION['validationcode']){<br />
			echo '提交成功<br>';<br />
		}else{ <br />
			echo '<font color="red">验证码输入错误！！</font><br>';<br />
		}<br />
	}<br />
?><br />
<html><br />
	<head><br />
		<title>Image</title><br />
		<meta http-equiv="content-type" content="text/html;charset=gb2312"><br />
		<script><br />
			function newgdcode(obj,url) {<br />
				//后面传递一个随机参数，否则在IE7和火狐下，不刷新图片<br />
				obj.src = url+ '?nowtime=' + new Date().getTime();<br />
			}<br />
		</script><br />
	</head><br />
	<body><br />
		<img src="/static/imghwm/default1.png"  data-src="imgcode.php"  class="lazy"   alt="看不清楚，换一张"   style="max-width:90%" onClick="javascript: newgdcode(this,this.src);" /><br />
		<form method="POST" action="image.php"><br />
			<input type="text" name="test"><br><br />
			<input type="submit" name="submit" value="提交"><br />
		</form><br />
	</body><br />
</html><br />

imgcode.php

<br />
<?php<br />
	session_start();<br />
	require_once('ValidationCode.php');<br />
<br />
	$image = new ValidationCode(60,20,4);    <br />
<br />
	$image->showImage();<br />
	$_SESSION['validationcode'] =$image->getCheckCode(); <br />
?><br />

ValidationCode.php

<br>
<?php <br />
     /* 类ValidationCode声明在文件名为Validationcode.php中    */<br>
     /* 通过该类的对象可以动态获取验证码图片，和验证码字符串 */<br>
	class ValidationCode {<br>
		private $width;                               //验证码图片的宽度<br>
		private $height;                               //验证码图片的高度<br>
		private $codeNum;                            //验证码字符的个数<br>
		private $checkCode;                           //验证码字符<br>
		private $image;                               //验证码画布<br>
<br>
		/* 构造方法用来实例化验证码对象，并为一些成员属性初使化        */<br>
		/* 参数width: 设置验证码图片的宽度，默认宽度值为60像素        */<br>
		/* 参数height: 设置验证码图片的高度，默认高度值为20像素        */<br>
		/* 参数codeNum: 设置验证码中字母和数字的个数，默认个数为4个  */<br>
		function __construct($width=60, $height=20, $codeNum=4) {<br>
			$this->width=$width;                     //为成员属性width初使化<br>
			$this->height=$height;                     //为成员属性height初使化<br>
			$this->codeNum=$codeNum;               //为成员属性codeNum初使化 <div class="clear">
                 
              
              
        
            </div>

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