harmony 鸿蒙@ohos.xml (XML Parsing and Generation)

  • 2022-08-09
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@ohos.xml (XML Parsing and Generation)

NOTE

The initial APIs of this module are supported since API version 8. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import xml from '@ohos.xml';

XmlSerializer

constructor

constructor(buffer: ArrayBuffer|DataView, encoding?: string)

A constructor used to create an XmlSerializer instance.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
buffer ArrayBuffer |DataView Yes ArrayBuffer or DataView for storing the XML information to set.
encoding string No Encoding format. The default value is ‘utf-8’ (the only format currently supported).

Example

let arrayBuffer = new ArrayBuffer(2048);
let thatSer = new xml.XmlSerializer(arrayBuffer, "utf-8");
thatSer.setDeclaration();
let result = '<?xml version="1.0" encoding="utf-8"?>';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(view1) // <?xml version="1.0" encoding="utf-8"?>

setAttributes

setAttributes(name: string, value: string): void

Sets an attribute.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
name string Yes Key of the attribute.
value string Yes Value of the attribute.

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.startElement("note");
thatSer.setAttributes("importance1", "high1");
thatSer.endElement();
let result = '<note importance1="high1"/>';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(view1) // <note importance1="high1"/>

addEmptyElement

addEmptyElement(name: string): void

Adds an empty element.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
name string Yes Name of the empty element to add.

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.addEmptyElement("d");
let result = '<d/>';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(view1) // <d/>

setDeclaration

setDeclaration(): void

Sets a declaration.

System capability: SystemCapability.Utils.Lang

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.setDeclaration();
thatSer.setNamespace("h", "http://www.w3.org/TR/html4/");
thatSer.startElement("note");
thatSer.endElement();
let result = '<?xml version="1.0" encoding="utf-8"?>\r\n<h:note xmlns:h="http://www.w3.org/TR/html4/"/>';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(view1)
// <?xml version="1.0" encoding="utf-8"?>
// <h:note xmlns:h="http://www.w3.org/TR/html4/"/>

startElement

startElement(name: string): void

Writes the start tag based on the given element name.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
name string Yes Name of the element.

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.setDeclaration();
thatSer.setNamespace("h", "http://www.w3.org/TR/html4/");
thatSer.startElement("note");
thatSer.endElement();
let result = '<?xml version="1.0" encoding="utf-8"?>\r\n<h:note xmlns:h="http://www.w3.org/TR/html4/"/>';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(JSON.stringify(view1)) // <?xml version="1.0" encoding="utf-8"?>\r\n<h:note xmlns:h="http://www.w3.org/TR/html4/"/>

endElement

endElement(): void

Writes the end tag of the element.

System capability: SystemCapability.Utils.Lang

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.setDeclaration();
thatSer.setNamespace("h", "http://www.w3.org/TR/html4/");
thatSer.startElement("note");
thatSer.endElement();
let result = '<?xml version="1.0" encoding="utf-8"?>\r\n<h:note xmlns:h="http://www.w3.org/TR/html4/"/>';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(JSON.stringify(view1)) // <?xml version="1.0" encoding="utf-8"?>\r\n<h:note xmlns:h="http://www.w3.org/TR/html4/"/>

setNamespace

setNamespace(prefix: string, namespace: string): void

Sets the namespace for an element tag.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
prefix string Yes Prefix of the element and its child elements.
namespace string Yes Namespace to set.

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.setDeclaration();
thatSer.setNamespace("h", "http://www.w3.org/TR/html4/");
thatSer.startElement("note");
thatSer.endElement();
let result = '<?xml version="1.0" encoding="utf-8"?>\r\n<h:note xmlns:h="http://www.w3.org/TR/html4/"/>';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(JSON.stringify(view1)) // <?xml version="1.0" encoding="utf-8"?>\r\n<h:note xmlns:h="http://www.w3.org/TR/html4/"/>

setComment

setComment(text: string): void

Sets a comment.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
text string Yes Comment to set.

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.setComment("Hello, World!");
let result = '<!--Hello, World!-->';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(view1) // <!--Hello, World!-->

setCDATA

setCDATA(text: string): void

Sets CDATA data.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
text string Yes CDATA data to set.

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.setCDATA('root SYSTEM')
let result = '<![CDATA[root SYSTEM]]>';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(view1) // <![CDATA[root SYSTEM]]>

setText

setText(text: string): void

Sets a tag value.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
text string Yes Tag value to set, which is the content of the text attribute.

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.startElement("note");
thatSer.setAttributes("importance", "high");
thatSer.setText("Happy1");
thatSer.endElement();
let result = '<note importance="high">Happy1</note>';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(view1) // <note importance="high">Happy1</note>

setDocType

setDocType(text: string): void

Sets a document type.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
text string Yes Content of DocType to set.

Example

const myMAX = 2048;
let arrayBuffer = new ArrayBuffer(myMAX);
let thatSer = new xml.XmlSerializer(arrayBuffer);
thatSer.setDocType('root SYSTEM "http://www.test.org/test.dtd"');
let result = '<!DOCTYPE root SYSTEM "http://www.test.org/test.dtd">';
let view = new Uint8Array(arrayBuffer);
let view1 = "";
for (let i = 0; i < result.length; ++i) {
    view1 = view1 + String.fromCodePoint(view[i]);
}
console.log(view1) // <!DOCTYPE root SYSTEM "http://www.test.org/test.dtd">

XmlPullParser

constructor

constructor(buffer: ArrayBuffer|DataView, encoding?: string)

Creates and returns an XmlPullParser object.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
buffer ArrayBuffer |DataView Yes XML text information to be parsed.
encoding string No Encoding format. The default value is ‘utf-8’ (the only format currently supported).

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<!DOCTYPE note [\n<!ENTITY foo "baa">]>' +
    '<note importance="high" logged="true">' +
    '    <![CDATA[\r\nfuncrion matchwo(a,6)\r\n{\r\nreturn 1;\r\n}\r\n]]>' +
    '    <!--Hello, World!-->' +
    '    <company>John &amp; Hans</company>' +
    '    <title>Happy</title>' +
    '    <title>Happy</title>' +
    '    <lens>Work</lens>' +
    '    <lens>Play</lens>' +
    '    <?go there?>' +
    '    <a><b/></a>' +
    '    <h:table xmlns:h="http://www.w3.org/TR/html4/">' +
    '        <h:tr>' +
    '            <h:td>Apples</h:td>' +
    '            <h:td>Bananas</h:td>' +
    '        </h:tr>' +
    '    </h:table>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer, 'UTF-8');
let str1 = '';
function func1(name: string, value: string) {
  str1 += name + value;
  return true;
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tagValueCallbackFunction:func1}
that.parse(options);
console.log(str1)
//   note [<!ENTITY foo "baa">]note    funcrion matchwo(a,6){return 1;}    Hello, World!    companyJohn amp;amp; Hanscompany    titleHappytitle    titleHappytitle    lensWorklens    lensPlaylens    go there    abba    h:table        h:tr            h:tdApplesh:td            h:tdBananash:td        h:tr    h:tablenote

parse

parse(option: ParseOptions): void

Parses XML information.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
option ParseOptions Yes Options for controlling and obtaining the parsed information.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.getDepth() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value:0 key:2 value:1 key:10 value:1 key:2 value:2 key:4 value:2 key:3 value:2 key:10 value:1 key:2 value:2 key:4 value:2 key:3 value:2 key:10 value:1 key:2 value:2 key:4 value:2 key:3 value:2 key:3 value:1 key:1 value:0
// Note:
// key indicates the event type, and value indicates the parsing depth. You can learn the specific parsed event based on EVENTTYPE. In this example, key: value means:
// 0(START_DOCUMENT):0 (START_DOCUMENT is being parsed, and the depth is 0), 2(START_TAG):1 (START_TAG is being parsed, and the depth is 1), 10(WHITESPACE):1 (WHITESPACE is being parsed, and the depth is 1), 2(START_TAG):2 (START_TAG is being parsed, and the depth is 2), ...

ParseOptions

Defines the XML parsing options.

System capability: SystemCapability.Utils.Lang

Name Type Mandatory Description
supportDoctype boolean No Whether to ignore the document type. The default value is false, indicating that the document type is parsed.
ignoreNameSpace boolean No Whether to ignore the namespace. The default value is false, indicating that the namespace is parsed.
tagValueCallbackFunction (name: string, value: string) =&gt; boolean No Callback used to return tagValue for parsing the tag and tag value. The default value is null, indicating that the tag and tag value are not parsed.
attributeValueCallbackFunction (name: string, value: string) =&gt; boolean No Callback used to return attributeValue for parsing the attribute and attribute value. The default value is null, indicating that the attribute and attribute value are not parsed.
tokenValueCallbackFunction (eventType: EventType, value: ParseInfo) =&gt; boolean No Callback used to return tokenValue for parsing the EventType and ParseInfo attributes. The default value is null, indicating that the EventType and ParseInfo attribute are not parsed.

ParseInfo

Provides APIs to manage the parsed XML information.

getColumnNumber

getColumnNumber(): number

Obtains the column line number, starting from 1.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
number Column number obtained.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.getColumnNumber() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value:1 key:2 value:77 key:10 value:81 key:2 value:88 key:4 value:93 key:3 value:101 key:10 value:105 key:2 value:111 key:4 value:115 key:3 value:122 key:10 value:126 key:2 value:132 key:4 value:136 key:3 value:143 key:3 value:150 key:1 value:299

getDepth

getDepth(): number

Obtains the depth of this element.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
number Depth obtained.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.getDepth() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value:0 key:2 value:1 key:10 value:1 key:2 value:2 key:4 value:2 key:3 value:2 key:10 value:1 key:2 value:2 key:4 value:2 key:3 value:2 key:10 value:1 key:2 value:2 key:4 value:2 key:3 value:2 key:3 value:1 key:1 value:0
// Note:
// key indicates the event type, and value indicates the parsing depth. You can learn the specific parsed event based on EVENTTYPE. In this example, key: value means:
// 0(START_DOCUMENT):0 (START_DOCUMENT is being parsed, and the depth is 0), 2(START_TAG):1 (START_TAG is being parsed, and the depth is 1), 10(WHITESPACE):1 (WHITESPACE is being parsed, and the depth is 1), 2(START_TAG):2 (START_TAG is being parsed, and the depth is 2), ...

getLineNumber

getLineNumber(): number

Obtains the current line number, starting from 1.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
number Line number obtained.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.getLineNumber() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value:1 key:2 value:1 key:10 value:1 key:2 value:1 key:4 value:1 key:3 value:1 key:10 value:1 key:2 value:1 key:4 value:1 key:3 value:1 key:10 value:1 key:2 value:1 key:4 value:1 key:3 value:1 key:3 value:1 key:1 value:1

getName

getName(): string

Obtains the name of this element.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
string Element name obtained.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.getName() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value: key:2 value:note key:10 value: key:2 value:title key:4 value: key:3 value:title key:10 value: key:2 value:todo key:4 value: key:3 value:todo key:10 value: key:2 value:todo key:4 value: key:3 value:todo key:3 value:note key:1 value:

getNamespace

getNamespace(): string

Obtains the namespace of this element.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
string Namespace obtained.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.getNamespace() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value: key:2 value: key:10 value: key:2 value: key:4 value: key:3 value: key:10 value: key:2 value: key:4 value: key:3 value: key:10 value: key:2 value: key:4 value: key:3 value: key:3 value: key:1 value:

getPrefix

getPrefix(): string

Obtains the prefix of this element.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
string Element prefix obtained.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.getPrefix() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value: key:2 value: key:10 value: key:2 value: key:4 value: key:3 value: key:10 value: key:2 value: key:4 value: key:3 value: key:10 value: key:2 value: key:4 value: key:3 value: key:3 value: key:1 value:

getText

getText(): string

Obtains the text of the current event.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
string Text content obtained.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += ' key:' + key + ' value:' + value.getText() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value:  key:2 value:  key:10 value:      key:2 value:  key:4 value:Happy  key:3 value:  key:10 value:      key:2 value:  key:4 value:Work  key:3 value:  key:10 value:      key:2 value:  key:4 value:Play  key:3 value:  key:3 value:  key:1 value:

isEmptyElementTag

isEmptyElementTag(): boolean

Checks whether the current element is empty.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
boolean Returns true if the element is empty; returns false otherwise.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.isEmptyElementTag() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value:false key:2 value:false key:10 value:false key:2 value:false key:4 value:false key:3 value:false key:10 value:false key:2 value:false key:4 value:false key:3 value:false key:10 value:false key:2 value:false key:4 value:false key:3 value:false key:3 value:false key:1 value:false

isWhitespace

isWhitespace(): boolean

Checks whether the current text event contains only whitespace characters.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
boolean Returns true if the text event contains only whitespace characters; returns false otherwise.

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.isWhitespace() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value:true key:2 value:false key:10 value:true key:2 value:true key:4 value:false key:3 value:true key:10 value:true key:2 value:true key:4 value:false key:3 value:true key:10 value:true key:2 value:true key:4 value:false key:3 value:true key:3 value:true key:1 value:true

getAttributeCount

getAttributeCount(): number

Obtains the number of attributes for the current start tag.

System capability: SystemCapability.Utils.Lang

Return value |Type|Description | |——|———————-| |number|Number of attributes obtained.|

Example

import util from '@ohos.util';
let strXml =
  '<?xml version="1.0" encoding="utf-8"?>' +
    '<note importance="high" logged="true">' +
    '    <title>Happy</title>' +
    '    <todo>Work</todo>' +
    '    <todo>Play</todo>' +
    '</note>';
let textEncoder = new util.TextEncoder();
let arrbuffer = textEncoder.encodeInto(strXml);
let that = new xml.XmlPullParser(arrbuffer.buffer);
let str = "";
function func(key: xml.EventType, value: xml.ParseInfo) {
  str += 'key:' + key + ' value:' + value.getAttributeCount() + ' ';
  return true; // Determines whether to continually parse, which is used to continue or terminate parsing.
}
let options: xml.ParseOptions = {supportDoctype:true, ignoreNameSpace:true, tokenValueCallbackFunction:func}
that.parse(options);
console.log(str);
// Output:
// key:0 value:0 key:2 value:2 key:10 value:0 key:2 value:0 key:4 value:0 key:3 value:0 key:10 value:0 key:2 value:0 key:4 value:0 key:3 value:0 key:10 value:0 key:2 value:0 key:4 value:0 key:3 value:0 key:3 value:0 key:1 value:0

EventType

Enumerates the event types.

System capability: SystemCapability.Utils.Lang

Name Value Description
START_DOCUMENT 0 Start document event.
END_DOCUMENT 1 End document event.
START_TAG 2 Start tag event.
END_TAG 3 End tag event.
TEXT 4 Text event.
CDSECT 5 CDATA section event.
COMMENT 6 XML comment event.
DOCDECL 7 XML document type declaration event.
INSTRUCTION 8 XML processing instruction event.
ENTITY_REFERENCE 9 Entity reference event.
WHITESPACE 10 Whitespace character event.

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