捕获和转换Web的工具

使用Node.js从网站捕获HTML表Node.js API

有多种转换HTML表的方法 into使用JSON,CSV和Excel电子表格 GrabzIt的Node.js 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 url_to_table, html_to_table or file_to_table 方法 save or save_to 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

此特定方法调用将转换指定URL网页中的第一个HTML表, intoa CSV文件。 此代码段将转换在指定网页或HTML输入中找到的第一个HTML表 intoa CSV文件。

client.url_to_table("https://www.tesla.com");
//Then call the save or save_to method
client.html_to_table("<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 save_to method
client.file_to_table("tables.html");
//Then call the save or save_to 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 tableNumberToInclude 属性。

var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"tableNumberToInclude":2};

client.url_to_table("https://www.tesla.com", options);
//Then call the save or save_to method
client.save_to("result.csv", function (error, id){
    //this callback is called once the capture is downloaded
    if (error != null){
        throw error;
    }
});
var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"tableNumberToInclude":2};

client.html_to_table("<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 save_to method
client.save_to("result.csv", function (error, id){
    //this callback is called once the capture is downloaded
    if (error != null){
        throw error;
    }
});
var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"tableNumberToInclude":2};

client.file_to_table("tables.html", options);
//Then call the save or save_to method
client.save_to("result.csv", function (error, id){
    //this callback is called once the capture is downloaded
    if (error != null){
        throw error;
    }
});

您还可以指定 targetElement 属性,将确保仅转换指定元素ID中的表。

var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"targetElement":"stocks_table"};

client.url_to_table("https://www.tesla.com", options);
//Then call the save or save_to method
client.save_to("result.csv", function (error, id){
    //this callback is called once the capture is downloaded
    if (error != null){
        throw error;
    }
});
var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"targetElement":"stocks_table"};

client.html_to_table("<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 save_to method
client.save_to("result.csv", function (error, id){
    //this callback is called once the capture is downloaded
    if (error != null){
        throw error;
    }
});
var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"targetElement":"stocks_table"};

client.file_to_table("tables.html", options);
//Then call the save or save_to method
client.save_to("result.csv", function (error, id){
    //this callback is called once the capture is downloaded
    if (error != null){
        throw error;
    }
});

另外,您也可以通过将true传递给 includeAllTables 属性,但是仅适用于JSON和XLSX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。

var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"format","xlsx","includeHeaderNames":true,"includeAllTables":true};

client.url_to_table("https://www.tesla.com", options);
//Then call the save or save_to method
client.save_to("result.xlsx", function (error, id){
    //this callback is called once the capture is downloaded
    if (error != null){
        throw error;
    }
});
var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"format","xlsx","includeHeaderNames":true,"includeAllTables":true};

client.html_to_table("<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 save_to method
client.save_to("result.xlsx", function (error, id){
    //this callback is called once the capture is downloaded
    if (error != null){
        throw error;
    }
});
var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"format","xlsx","includeHeaderNames":true,"includeAllTables":true};

client.file_to_table("tables.html", options);
//Then call the save or save_to method
client.save_to("result.xlsx", function (error, id){
    //this callback is called once the capture is downloaded
    if (error != null){
        throw error;
    }
});

将HTML表转换为JSON

通过使用Node.js和GrabzIt,您可以转换HTML表 into JSON,只需指定 json 在format参数中。 如下面的示例所示, save_to 方法完成后,在结果变量中使用JSON调用oncomplete函数,然后由内置Node.js对其进行解析 JSON.parse 函数创建代表HTML表的对象。

var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"format","json","includeHeaderNames":true,"includeAllTables":true};
client.url_to_table("https://www.tesla.com", options);

client.save_to(null, function(error, result){
    if (result != null)
    {
        var tableObj = JSON.parse(result);
    }
});

自订识别码

您可以将自定义标识符传递给 方法,如下所示,然后将此值返回到GrabzIt Node.js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。

var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"customId":123456};

client.url_to_table("https://www.tesla.com", options);
//Then call the save method
client.save("http://www.example.com/handler", function (error, id){
    if (error != null){
        throw error;
    }
});
var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"customId":123456};

client.html_to_table("<html><body><h1>Hello World!</h1></body></html>", options);
//Then call the save method
client.save("http://www.example.com/handler", function (error, id){
    if (error != null){
        throw error;
    }
});
var grabzit = require('grabzit');

var client = new grabzit("Sign in to view your Application Key", "Sign in to view your Application Secret");

var options = {"customId":123456};

client.file_to_table("example.html", options);
//Then call the save method
client.save("http://www.example.com/handler", function (error, id){
    if (error != null){
        throw error;
    }
});