digital
// Convert a string to an integer or a double floating-point object using the parse() method of int and double:
print(int.parse(The '42') = =42); // true
print(int.parse('0x42') = =66); // true
print(double.parse('0.50') = =0.5); // true
// Specify the base base of integers by adding the radix parameter
print(int.parse(The '42', radix: 16) = =66); // true
// Use the toString() method to convert an integer or a double floating-point type to a string.
print(42.toString() == The '42'); // true
print(123.456.toString() == '123.456'); // true
// Use toStringAsFixed(). Specify the number to the right of the decimal point
print(123.456.toStringAsFixed(2) = ='123.46'); // true
// Use toStringAsPrecision(): Specifies the number of significant digits in the string
print(123.456.toStringAsPrecision(2) = ='1.2 e+2'); // true
print(double.parse('1.2 e+2') = =120.0); // true
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string
// Check if one string contains another string
print('Never odd or even'.contains('odd')); // true
// Checks if the string starts with a specific string
print('Never odd or even'.startsWith('Never')); // true
// Checks if the string ends with a specific string
print('Never odd or even'.endsWith('even')); // true
// Find the position of a particular string within the string
print('Never odd or even'.indexOf('odd') = =6); // true
// Intercepts a string
print('Never odd or even'.substring(6.9) = ='odd'); // true
// Split the string
print('structured web apps'.split(' ')); // [structured, web, apps]
print('hello'.split(' ')); // [h, e, l, l, o]
// Gets a single character in a string
print('Never odd or even'[0] = ='N'); // true
// Get a single UTF-16 encoding unit
var codeUnitList = 'Never odd or even'.codeUnits.toList();
print(codeUnitList); // [78, 101, 118, 101, 114, 32, 111, 100, 100, 32, 111, 114, 32, 101, 118, 101, 110]
// Case conversion.
print('structured web apps'.toUpperCase()); // STRUCTURED WEB APPS
print('STRUCTURED WEB APPS'.toLowerCase()); // structured web apps
// Use trim() to remove leading and trailing Spaces
print(' hello '.trim()); // 'hello'
// isEmpty checks if a string isEmpty (length 0)
print(' '.isEmpty); // true
print(' '.isNotEmpty); // true
// String substitution
var str = 'Hello, NAME, NAME! ';
// Replace the first matching
var str1 = str.replaceFirst(RegExp('NAME'), 'Bob');
// Replace all matches
var str2 = str.replaceAll(RegExp('NAME'), 'Bob');
// Specify range replacement
var str3 = str.replaceRange(7.11.'Bob');
print(str1); // Hello, Bob, NAME!
print(str2); // Hello, Bob, Bob!
print(str3); // Hello, Bob, NAME!
// Construct a string
var sb = StringBuffer(a); sb .. write('Use a StringBuffer for ')
..writeAll(['efficient'.'string'.'creation'].' ')
..write('. ');
print(sb.toString()); // Use a StringBuffer for efficient string creation.
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