getThreads（）for Gmail在Google Apps中返回NULL

Question

我試圖從以前的舊版羣組發帖中獲取以下Google Apps腳本以進行工作。它基本上正在調用getThreads（n，m）的地方。返回的錯誤代碼是：

TypeError：無法調用null的方法「addToThreads」。

有沒有更簡單的方法來調試getThreads（）函數？目標是將標籤從EVERNOTE更改爲Scripts/Forward。

// Set up multiple labels/sub-labels and add one or more email addresses 
function forwardEmails() { 
    forwardThreads("EVERNOTE", "username@m.evernote.com", "@Filtered Email Archive"); 
// forwardThreads("Forward/MoreItems", "username1@gmail.com, username2@gmail.com", "MORE INFO"); 
    } 

function forwardThreads(label, addr, subjSuffix) { 

    var maxSubjLength = 250; 
    var applylabel = GmailApp.getUserLabelByName("Scripts/Forward"); 

    // Send individual and threaded emails. 
    var msgs, msg, i, j, subject, options, labels, page; 
    labels = GmailApp.getUserLabelByName(label) 
    var threads = labels.getThreads() 
    for (i=0; i < threads.length; i++) { 
    msgs = threads[i].getMessages(); 
    for (j=0; j < msgs.length; j++) { 
     msg = msgs[j]; 

     subject = msg.getSubject(); 
     if (subject.length + subjSuffix.length > maxSubjLength) { 
     subject = subject.substring(0, maxSubjLength - subjSuffix.length); 
     } 

     options = { htmlBody: msg.getBody(), attachments : msg.getAttachments() }; 

     GmailApp.sendEmail(addr, subject +" "+ subjSuffix, msg.getBody(), options); 

    } 
    } 

    while(!page || page.length == 100) { 
    page = labels.getThreads(0, 100); 

    // Apply new label; move the thread out of other label 
    applylabel.addToThreads(page); // ***** Failing on this line - assume page is NULL 
    labels.removeFromThreads(page); 
     } 
} 

Answer 1

該錯誤消息TypeError: Cannot call method "addToThreads" of null.，在該代碼中，意味着該applylabel變量是null。只有當GmailApp.getUserLabelByName("Scripts/Forward");返回null，並且如果系統找不到Scripts/Forward標籤，就會發生這種情況。我假設用戶身份運行腳本沒有這樣的標籤。