@ohos.data.uniformTypeDescriptor (Uniform Data Definition and Description)

The uniformTypeDescriptor module abstracts and defines uniform data types.

NOTE

The initial APIs of this module are supported since API version 10. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import { uniformTypeDescriptor } from '@kit.ArkData';

UniformDataType

Enumerates the uniform data types. Some data types are related. For example, the JPEG type belongs to the IMAGE type. For more preset data types, see Preset UTD List.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

TypeDescriptor¹¹⁺

Represents a class for defining a uniform data type. It provides properties and methods for describing a uniform data type and its relationship with other uniform data types.

Properties

System capability: SystemCapability.DistributedDataManager.UDMF.Core

belongsTo¹¹⁺

belongsTo(type: string): boolean

Checks whether this data type belongs to the specified uniform data type.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Return value

Error codes

For details about the error codes, see Universal Error Codes.

Example

import { uniformTypeDescriptor } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';

try{
    let typeObj : uniformTypeDescriptor.TypeDescriptor = uniformTypeDescriptor.getTypeDescriptor('general.type-script');
    let ret = typeObj.belongsTo('general.source-code');
    if(ret) {
        console.info('type general.type-script belongs to type general.source-code');
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`belongsTo throws an exception. code is ${error.code}, message is ${error.message} `);
}

isLowerLevelType¹¹⁺

isLowerLevelType(type: string): boolean

Checks whether this data type is a lower-level type of the specified uniform data type. For example, TYPE_SCRIPT is a lower-level type of SOURCE_CODE, and TYPE_SCRIPT and SOURCE_CODE are lower-level types of TEXT.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Return value

Error codes

For details about the error codes, see Universal Error Codes.

Example

import { uniformTypeDescriptor } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';

try{
    let typeObj : uniformTypeDescriptor.TypeDescriptor = uniformTypeDescriptor.getTypeDescriptor('general.type-script');
    let ret = typeObj.isLowerLevelType('general.source-code');
    if(ret) {
        console.info('type general.type-script is lower level type of type general.source-code');
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`isLowerLevelType throws an exception. code is ${error.code}, message is ${error.message} `);
}

isHigherLevelType¹¹⁺

isHigherLevelType(type: string): boolean

Checks whether this data type is a higher-level type of the specified uniform data type. For example, SOURCE_CODE is a higher-level type of TYPE_SCRIPT, and TEXT is a higher-level type of SOURCE_CODE and TYPE_SCRIPT.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Return value

Error codes

For details about the error codes, see Universal Error Codes.

Example

import { uniformTypeDescriptor } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';

try{
    let typeObj : uniformTypeDescriptor.TypeDescriptor = uniformTypeDescriptor.getTypeDescriptor('general.source-code');
    let ret = typeObj.isHigherLevelType('general.type-script');
    if(ret) {
        console.info('type general.source-code is higher level type of type general.type-script');
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`isHigherLevelType throws an exception. code is ${error.code}, message is ${error.message} `);
}

equals¹¹⁺

equals(typeDescriptor: TypeDescriptor): boolean

Checks whether this data type is the same as the specified uniform data type. That is, compares typeIds of two TypeDescriptor objects.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Return value

Error codes

For details about the error codes, see Universal Error Codes.

Example

import { uniformTypeDescriptor } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';

try{
    let typeA : uniformTypeDescriptor.TypeDescriptor = uniformTypeDescriptor.getTypeDescriptor('general.type-script');
    let typeB : uniformTypeDescriptor.TypeDescriptor = uniformTypeDescriptor.getTypeDescriptor('general.python-script');
    if(!typeA.equals(typeB)) {
      console.info('typeA is not equal to typeB');
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`throws an exception. code is ${error.code}, message is ${error.message} `);
}

uniformTypeDescriptor.getTypeDescriptor¹¹⁺

getTypeDescriptor(typeId: string): TypeDescriptor

Obtains the TypeDescriptor object based on the uniform data type ID.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Return value

Error codes

For details about the error codes, see Universal Error Codes.

Example

import { uniformTypeDescriptor } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';

try {
    let typeObj : uniformTypeDescriptor.TypeDescriptor = uniformTypeDescriptor.getTypeDescriptor('com.adobe.photoshop-image');
    if (typeObj) {
        let typeId = typeObj.typeId;
        let belongingToTypes = typeObj.belongingToTypes;
        let description = typeObj.description;
        let referenceURL = typeObj.referenceURL;
        let iconFile = typeObj.iconFile;
        let filenameExtensions = typeObj.filenameExtensions;
        let mimeTypes = typeObj.mimeTypes;
        console.info(`typeId: ${typeId}, belongingToTypes: ${belongingToTypes}, description: ${description}, referenceURL: ${referenceURL}, iconFile: ${iconFile}, filenameExtensions: ${filenameExtensions}, mimeTypes: ${mimeTypes}`);
    } else {
        console.info('type com.adobe.photoshop-image does not exist');
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`getTypeDescriptor throws an exception. code is ${error.code}, message is ${error.message} `);
}

uniformTypeDescriptor.getUniformDataTypeByFilenameExtension¹¹⁺

getUniformDataTypeByFilenameExtension(filenameExtension: string, belongsTo?: string): string

Obtains the uniform data type ID based on the given file name extension and data type. If there are multiple uniform data type IDs matching the conditions, the first one is returned.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Return value

Error codes

For details about the error codes, see Universal Error Codes.

Example

import { uniformTypeDescriptor } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';

try {
    let typeId = uniformTypeDescriptor.getUniformDataTypeByFilenameExtension('.ts', 'general.source-code');
    if(typeId) {
        console.info('typeId is general.type-script');
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`getUniformDataTypeByFilenameExtension throws an exception. code is ${error.code}, message is ${error.message} `);
}

// If no uniform data type ID is found based on ".myts" and "general.plain-text", the type generated based on the input parameters is returned.
try {
    let typeId = uniformTypeDescriptor.getUniformDataTypeByFilenameExtension('.myts', 'general.plain-text');
    if(typeId) {
        console.info('typeId is flex.************');
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`getUniformDataTypeByFilenameExtension throws an exception. code is ${error.code}, message is ${error.message} `);
}

uniformTypeDescriptor.getUniformDataTypeByMIMEType¹¹⁺

getUniformDataTypeByMIMEType(mimeType: string, belongsTo?: string): string

Obtains the uniform data type ID based on the given MIME type and data type. If there are multiple uniform data type IDs matching the conditions, the first one is returned.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Return value

Error codes

For details about the error codes, see Universal Error Codes.

Example

import { uniformTypeDescriptor } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';

try {
    let typeId = uniformTypeDescriptor.getUniformDataTypeByMIMEType('image/jpeg', 'general.image');
    if(typeId) {
        console.info('typeId is general.jpeg');
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`getUniformDataTypeByMIMEType throws an exception. code is ${error.code}, message is ${error.message} `);
}

// If no uniform data type ID is found based on "image/myimage" and "general.image", the type generated based on the input parameters is returned.
try {
    let typeId = uniformTypeDescriptor.getUniformDataTypeByMIMEType('image/myimage', 'general.image');
    if(typeId) {
        console.info('typeId is flex.************');
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`getUniformDataTypeByMIMEType throws an exception. code is ${error.code}, message is ${error.message} `);
}

uniformTypeDescriptor.getUniformDataTypesByFilenameExtension¹³⁺

getUniformDataTypesByFilenameExtension(filenameExtension: string, belongsTo?: string): Array<string>

Obtains the uniform data type IDs based on the given file name extension and data type.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Return value

Error codes

For details about the error codes, see Universal Error Codes.

Example

import { uniformTypeDescriptor } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';

try {
    let typeIds = uniformTypeDescriptor.getUniformDataTypesByFilenameExtension('.ts', 'general.source-code');
    for (let typeId of typeIds) {
        console.info(`typeId is ${typeId}`);
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`getUniformDataTypesByFilenameExtension throws an exception. code is ${error.code}, message is ${error.message} `);
}

// If no uniform data type ID is found based on ".myts" and "general.plain-text", the types generated based on the input parameters are returned.
try {
    let flexTypeIds = uniformTypeDescriptor.getUniformDataTypesByFilenameExtension('.myts', 'general.plain-text');
    for (let flexTypeId of flexTypeIds) {
        console.info(`typeId is flex type, flex typeId is ${flexTypeId}`);
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`getUniformDataTypesByFilenameExtension throws an exception. code is ${error.code}, message is ${error.message} `);
}

uniformTypeDescriptor.getUniformDataTypesByMIMEType¹³⁺

getUniformDataTypesByMIMEType(mimeType: string, belongsTo?: string): Array<string>

Obtains the uniform data type IDs based on the given MIME type and data type.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Return value

Error codes

For details about the error codes, see Universal Error Codes.

Example

import { uniformTypeDescriptor } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';

try {
    let typeIds = uniformTypeDescriptor.getUniformDataTypesByMIMEType('text/plain', 'general.text');
    for (let typeId of typeIds) {
        console.info(`typeId is ${typeId}`);
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`getUniformDataTypesByMIMEType throws an exception. code is ${error.code}, message is ${error.message} `);
}

// If no uniform data type ID is found based on "image/myimage" and "general.image", the types generated based on the input parameters are returned.
try {
    let flexTypeIds = uniformTypeDescriptor.getUniformDataTypesByMIMEType('image/myimage', 'general.image');
    for (let flexTypeId of flexTypeIds) {
        console.info(`typeId is flex type, flex typeId is ${flexTypeId}`);
    }
} catch(e) {
    let error: BusinessError = e as BusinessError;
    console.error(`getUniformDataTypesByMIMEType throws an exception. code is ${error.code}, message is ${error.message} `);
}

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