I can not convert a String to a Boolean

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I can not convert a String to a Boolean

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#1 by (1 votes)

-1

I am with a form, in C # with the MVC structure, and I can not convert the string to bool , it is assumed that the code to write must be done from the controller and in the html

<form>

    <div class="editor-label">
        @Html.LabelFor(model => model.TRABAJO)
    </div>

    <div class="editor-field">
        @Html.EditorFor(model => model.TRABAJO)
        @Html.ValidationMessageFor(model => model.TRABAJO)
    </div>

    <div class="editor-label">
        @Html.LabelFor(model => model.ESTUDIANTE)
    </div>

    <div class="editor-field">
        @Html.EditorFor(model => model.ESTUDIANTE)
        @Html.ValidationMessageFor(model => model.ESTUDIANTE)
    </div>

</form>

c# mvc asp.net-mvc

asked by DC-Rom 02.10.2018 в 21:00

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1 answer

Problems with obtaining location in android studio Problem with the IF in java

score 1 · Answer 1

C # does not allow implicit string conversion to Boolean, since the Boolean variable can only have the values True or False and the string can have millions of different characters.

I suppose that the string you want to convert to a boolean contains: "True" or "False", so, to evaluate if the string can be converted to a boolean, you must use the static method tryParse implemented by all primitive data types .

for example:

using System;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            const string miValorVerdero = "True";
            const string miValorFalso = "False";
            const string miNombre = "Juan";

            if (bool.TryParse(miValorVerdero, out var miVariableBooleana))
            {
                Console.WriteLine("Se puede convertir miValorVerdero");
                Console.WriteLine($"el valor de miVariableBooleana es: {miVariableBooleana}");

            }
            else
            {
                Console.WriteLine("NO Se pudo convertir miValorVerdero");
            }

            if (bool.TryParse(miValorFalso, out miVariableBooleana))
            {
                Console.WriteLine("Se pudo convertir miValorFalso");
                Console.WriteLine($"el valor de miVariableBooleana: {miVariableBooleana}");

            }
            else
            {
                Console.WriteLine("NO Se pudo convertir miValorFalso");
            }

            if (bool.TryParse(miNombre, out miVariableBooleana))
            {
                Console.WriteLine("Se pudo convertir miNombre");
                Console.WriteLine($"el valor de miVariableBooleana: {miVariableBooleana}");

            }
            else
            {
                Console.WriteLine("NO se pudo convertir miNombre");
            }

            Console.Read();
        }
    }
}

// Output:
// Se puede convertir miValorVerdero
// el valor de miVariableBooleana es: True
// Se pudo convertir miValorFalso
// el valor de miVariableBooleana: False
// NO se pudo convertir miNombre

You can also develop your own method to determine if a string can be converted to boolean by following your own rules. Ex:

public static bool ConvertirStrBool(string cadena)
    {
        switch (cadena.ToLower())
        {
            case "true":
                return true;
            case "t":
                return true;
            case "1":
                return true;
            case "0":
                return false;
            case "false":
                return false;
            case "f":
                return false;
            default:
                throw new InvalidCastException("Este valor no se puede convertir a bool!");
        }
    }