For simplicity, the php file and form are written in one file.
php single file upload---->
<span> 1</span> <!DOCTYPE html>
<span> 2</span> <html>
<span> 3</span> <head>
<span> 4</span> <meta charset="UTF-8" />
<span> 5</span> </head>
<span> 6</span> <body>
<span> 7</span> <form action="upload.php" method="post" enctype="multipart/form-data">
<span> 8</span> 请选择要上传的文件:<input type="file" name="myfile"/><br /><br />
<span> 9</span> <input type="submit" value="submit" />
<span>10</span> <input type="hidden" name="MAX_FILE_SIZE" value="5982"/>
<span>11</span> </form>
<span>12</span> </body>
<span>13</span> </html>
<span>14</span>
<span>15</span>
<span>16</span>
<span>17</span> <?<span>php
</span><span>18</span> <span>if</span>(!<span>empty</span>(<span>$_FILES</span><span>)){
</span><span>19</span> <span>header</span>('content-type:text/html;charset=utf-8'<span>);
</span><span>20</span> <span>$fileInfo</span>=<span>$_FILES</span>['myfile'<span>];
</span><span>21</span> <span>print_r</span>(<span>$_FILES</span><span>);
</span><span>22</span> <span>//</span><span>如果上传出错则退出并打印错误信息</span>
<span>23</span> <span>if</span>(<span>$fileInfo</span>['error']>0<span>){
</span><span>24</span> <span>switch</span>(<span>$fileInfo</span>['error'<span>]){
</span><span>25</span> <span>case</span> 1:
<span>26</span> <span>$msg_error</span>='上传文件超过了php配置文件中UPLOAD_MAX_FILESIZE选项的值'<span>;
</span><span>27</span> <span>break</span><span>;
</span><span>28</span> <span>case</span> 2:
<span>29</span> <span>$msg_error</span>='超过了表单MAX_FILE_SIZE限制的大小'<span>;
</span><span>30</span> <span>break</span><span>;
</span><span>31</span> <span>case</span> 3:
<span>32</span> <span>$msg_error</span>='文件部分上传'<span>;
</span><span>33</span> <span>break</span><span>;
</span><span>34</span> <span>case</span> 4:
<span>35</span> <span>$msg_error</span>='没有文件上传'<span>;
</span><span>36</span> <span>break</span><span>;
</span><span>37</span> <span>case</span> 6:
<span>38</span> <span>$msg_error</span>='没有找到临时目录'<span>;
</span><span>39</span> <span>break</span><span>;
</span><span>40</span> <span>case</span> 7:
<span>41</span> <span>case</span> 8:
<span>42</span> <span>$msg_error</span>='系统错误'<span>;
</span><span>43</span> <span>break</span><span>;
</span><span>44</span> <span> }
</span><span>45</span> <span>exit</span>(<span>$msg_error</span><span>);
</span><span>46</span> <span> }
</span><span>47</span> <span>$filename</span>=<span>$fileInfo</span>['name'<span>];
</span><span>48</span> <span>//</span><span>获取文件的扩展名</span>
<span>49</span> <span>$ext</span>=<span>strtolower</span>(<span>substr</span>(<span>$filename</span>,<span>strrpos</span>(<span>$filename</span>,'.')+1<span>));
</span><span>50</span> <span>//</span><span>定义可允许上传的扩展名</span>
<span>51</span> <span>$allowExt</span>=<span>array</span>('txt','html','png','gif','jpeg'<span>);
</span><span>52</span> <span>//</span><span>检测上传文件的类型</span>
<span>53</span> <span>if</span>(!<span>in_array</span>(<span>$ext</span>,<span>$allowExt</span><span>)){
</span><span>54</span> <span>exit</span>('上传文件类型错误'<span>);
</span><span>55</span> <span> }
</span><span>56</span>
<span>57</span>
<span>58</span> <span>//</span><span>检测文件的大小</span>
<span>59</span> <span>$maxSize</span>=2097152<span>;
</span><span>60</span> <span>if</span>(<span>$fileInfo</span>['size']><span>$maxSize</span><span>){
</span><span>61</span> <span>exit</span>('上传文件过大'<span>);
</span><span>62</span> <span> }
</span><span>63</span>
<span>64</span> <span>//</span><span>检测是否为HTTP POST方式上传上来的</span>
<span>65</span> <span>if</span>(!<span>is_uploaded_file</span>(<span>$fileInfo</span>['tmp_name'<span>])){
</span><span>66</span> <span>exit</span>('文件不是通过HTTP POST方式提交上来的'<span>);
</span><span>67</span> <span> }
</span><span>68</span>
<span>69</span> <span>//</span><span>确保文件名字唯一,防止同名文件被覆盖</span>
<span>70</span> <span>$uniqName</span>=<span>md5</span>(<span>uniqid</span>(<span>microtime</span>(<span>true</span>),<span>true</span>)).'.'.<span>$ext</span><span>;
</span><span>71</span>
<span>72</span> <span>//</span><span>定义保存在哪个文件夹下,如果没有该文件夹则创建</span>
<span>73</span> <span>$path</span>='uploads'<span>;
</span><span>74</span> <span>if</span>(!<span>file_exists</span>(<span>$path</span><span>)){
</span><span>75</span> <span>mkdir</span>(<span>$path</span>,0777,<span>true</span><span>);
</span><span>76</span> <span>chmod</span>(<span>$path</span>,0777<span>);
</span><span>77</span> <span> }
</span><span>78</span> <span>$destination</span>=<span>$path</span>.'/'.<span>$uniqName</span><span>;
</span><span>79</span>
<span>80</span> <span>//</span><span>移动文件至要保存的目录</span>
<span>81</span> <span>if</span>(! @<span>move_uploaded_file</span>(<span>$fileInfo</span>['tmp_name'],<span>$destination</span><span>)){
</span><span>82</span> <span>exit</span>('文件上传失败'<span>);
</span><span>83</span> <span> }
</span><span>84</span>
<span>85</span> <span>echo</span> '上传成功'<span>;
</span><span>86</span>
<span>87</span> <span> }
</span><span>88</span> ?>
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