Flutter function return string Jan 17, 2021 · How can i return a string from a future function? Future<String> functionA() async { var x = await fetchX(); return x; } Future<String> fetchX() { return Future. delayed(Dur Jun 4, 2025 · The type String Function(int) is the type of a function that takes one positional int argument and returns a String. I have a FutureBuilder that waits on an async function to return a string. These functions are called anonymous functions, lambdas, or closures. An anonymous function resembles a named function as it has: Zero or more parameters, comma-separated; Optional type annotations between parentheses. This is displayed as output. The problem is, when I format the answer I end up with a String and I have to return it as answerString as Future<String>. Lets take an example to understand how returning functions work. isEmpty(): returns true if string is empty. The function test() returns a string. The functions return type is string. Dec 15, 2019 · replaceRange(): returns new string which is substring from start to end index with string to be replaced. isNonEmpty(): returns true if string is not empty. Example with generic function type: T id<T>(T value) => value; X Function<X>(X) anotherId = id; // Parameter name may be omitted. toUpperCase() and toLowerCase() methods return a new string (not change the original string) with all letters have been converted to uppercase or lowercase format: May 6, 2025 · Though you name most functions, such as main() or printElement(). int Function(int) intId = id<int>; Mar 16, 2022 · Dart/Flutter transform String functions Upper and Lower String. . you can also create functions without names. I call the back, and get the answer and format it before returning it and if the back fails, I asynchronously read files to fill the gap. The example declares a function test(). This is achieved by the return statement. The function returns a string value to the caller. pfnt muqhbkmp lqsubp yhs yloom fpjl fhfre xafd opsmjye abtwmht