捕获和转换Web的工具

使用Java从网站捕获HTML表

Java API

有多种转换HTML表的方法 into使用JSON,CSV和Excel电子表格 GrabzIt的Java API,这里详细介绍了一些最有用的技术。 但是,在开始之前,请记住 URLToTable, HTMLToTable or 文件到表格 方法 Save or SaveTo 必须调用方法来捕获表。 如果您想快速查看此服务是否适合您,可以尝试 捕获HTML表的实时演示 从URL。

基本选项

此代码段将转换在指定网页中找到的第一个HTML表 intoa CSV文件。

grabzIt.URLToTable("https://www.tesla.com");
//Then call the Save or SaveTo method
grabzIt.HTMLToTable("<html><body><table><tr><th>Name</th><th>Age</th></tr>
    <tr><td>Tom</td><td>23</td></tr><tr><td>Nicola</td><td>26</td></tr>
    </table></body></html>");
//Then call the Save or SaveTo method
grabzIt.FileToTable("tables.html");
//Then call the Save or SaveTo method

默认情况下,它将转换它标识的第一个表 intoa表。 但是,可以通过将2传递给网页中的第二个表来进行转换 setTableNumberToInclude 的方法 TableOptions 类。

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTableNumberToInclude(2);

grabzIt.URLToTable("https://www.tesla.com", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");
GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTableNumberToInclude(2);

grabzIt.HTMLToTable("<html><body><table><tr><th>Name</th><th>Age</th></tr>
    <tr><td>Tom</td><td>23</td></tr><tr><td>Nicola</td><td>26</td></tr>
    </table></body></html>", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");
GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTableNumberToInclude(2);

grabzIt.FileToTable("tables.html", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");

您也可以使用 setTargetElement 确保只转换指定元素ID中的表的方法。

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTargetElement("stocks_table");

grabzIt.URLToTable("https://www.tesla.com", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");
GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTargetElement("stocks_table");

grabzIt.HTMLToTable("<html><body><table id='stocks_table'><tr><th>Name</th><th>Age</th></tr>
    <tr><td>Tom</td><td>23</td></tr><tr><td>Nicola</td><td>26</td></tr>
    </table></body></html>", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");
GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTargetElement("stocks_table");

grabzIt.FileToTable("tables.html", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");

另外,您也可以通过将true传递给 setIncludeAllTables 方法,但是仅适用于XLSX和JSON格式。 此选项会将每个表放在生成的电子表格工作簿中的新表中。

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setFormat(TableFormat.XLSX);
options.setIncludeAllTables(true);

grabzIt.URLToTable("https://www.tesla.com", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.xlsx");
GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setFormat(TableFormat.XLSX);
options.setIncludeAllTables(true);

grabzIt.HTMLToTable("<html><body><table><tr><th>Name</th><th>Age</th></tr>
    <tr><td>Tom</td><td>23</td></tr><tr><td>Nicola</td><td>26</td></tr>
    </table></body></html>", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.xlsx");
GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setFormat(TableFormat.XLSX);
options.setIncludeAllTables(true);

grabzIt.FileToTable("tables.html", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.xlsx");

将HTML表转换为JSON

GrabzIt还可以将在Web上找到的HTML表转换为JSON,只需指定JSON格式即可。 在下面的示例中,数据被同步读取,并以 GrabzItFile 通过使用对象 SaveTo 方法,但是通常建议您执行此操作 异步.

转换完成后, toString 调用方法以获取JSON作为 string,然后可以通过类似的库进行解析 谷歌gson.

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setFormat(TableFormat.JSON);
options.setTableNumberToInclude(1);

grabzIt.URLToTable("https://www.tesla.com", options);

GrabzItFile file = grabzIt.SaveTo();
if (file != null)
{
    String json = file.toString();
}

自订识别码

您可以将自定义标识符传递给 方法,如下所示,然后将该值返回到您的GrabzIt Java处理程序。 例如,此自定义标识符可以是数据库标识符,从而允许将屏幕截图与特定的数据库记录相关联。

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setCustomId("123456");

grabzIt.URLToTable("https://www.tesla.com", options);
//Then call the Save method
grabzIt.Save("http://www.example.com/handler");
GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setCustomId("123456");

grabzIt.HTMLToTable("<html><body><h1>Hello World!</h1></body></html>", options);
//Then call the Save method
grabzIt.Save("http://www.example.com/handler");
GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setCustomId("123456");

grabzIt.FileToTable("example.html", options);
//Then call the Save method
grabzIt.Save("http://www.example.com/handler");