This is machine translation

Translated by Microsoft
Mouseover text to see original. Click the button below to return to the English version of the page.

Note: This page has been translated by MathWorks. Click here to see
To view all translated materials including this page, select Country from the country navigator on the bottom of this page.



Return message header fields matching name or class


[fields,indices] = getFields(messages,ids)



[fields,indices] = getFields(messages,ids) returns fields and their indices in the messages that match the given IDs.

Input Arguments

expand all

Messages, specified as a vector of objects.

Example: getFields([msg1,msg2],'Date')

Names to match, specified as one of the following.

  • String vector, character vector, cell array of character vectors, or comma-separated list of strings or character vectors containing the names of the fields to return. Names are not case-sensitive.

  • Vector or comma-separated list of one or more objects whose Name properties are used to determine which fields to return. Names are not case-sensitive. Header field values in these objects are ignored.

  • Vector or comma-separated list of meta.class objects that are subclasses of HeaderField.

    The getFields method searches for names that match names supported by the specified classes, regardless of the class. If a subclass does not have a specific set of supported names, all header fields of that subclass are matched regardless of their names. Call the HeaderField.displaySubclasses method to see supported names.

Example: getFields(response,'Date','Content-Type')

Output Arguments

expand all

Fields matching input, returned as an array of objects. If no matches exist, getFields returns an empty HeaderField array. The name search is case-insensitive.

Index values of fields, returned as an array of integers, or [] if no match.

If messages is a vector, then getFields returns fields matching ids from all messages. indices is a cell array of vectors, where indices{i} contains the indices of the matching fields in messages{i}.


expand all

Add a missing Date header field to a request message using the RequestMessage.complete method.

Create a request message to get text from the MathWorks website.

uri ='');
req =;

Verify the message contains a Date field. The date value reflects your system information. The value indices{1} = [] indicates that req does not contain a Date field.

request = complete(req,uri);
[fields,indices] = getFields([req,request],?
fields = 
  DateField with properties:

     Name: "Date"
    Value: "Sat, 13 Apr 2019 04:06:05 GMT"

indices = 1x2 cell array
    {0x0 double}    {[3]}

Introduced in R2016b