Version.TryParse 方法
定义
重载
| TryParse(ReadOnlySpan<Char>, Version) |
尝试将表示版本号的指定字符只读范围转换为等效的 Version 对象,并返回一个指示转换是否成功的值。Tries to convert the specified read-only span of characters representing a version number to an equivalent Version object, and returns a value that indicates whether the conversion succeeded. |
| TryParse(String, Version) |
尝试将版本号的字符串表示形式转换为等效的 Version 对象,并返回一个指示转换是否成功的值。Tries to convert the string representation of a version number to an equivalent Version object, and returns a value that indicates whether the conversion succeeded. |
TryParse(ReadOnlySpan<Char>, Version)
public:
static bool TryParse(ReadOnlySpan<char> input, [Runtime::InteropServices::Out] Version ^ % result);
public static bool TryParse (ReadOnlySpan<char> input, out Version? result);
public static bool TryParse (ReadOnlySpan<char> input, out Version result);
static member TryParse : ReadOnlySpan<char> * Version -> bool
Public Shared Function TryParse (input As ReadOnlySpan(Of Char), ByRef result As Version) As Boolean
参数
- input
- ReadOnlySpan<Char>
字符的只读范围,其中包含要转换的版本号。A read-only span of characters that contains a version number to convert.
- result
- Version
当此方法返回时,如果转换成功,则为 input 总所含数字的等效 Version。When this method returns, the Version equivalent of the number that is contained in input, if the conversion succeeded. 如果 input 为 null、Empty 或者如果转换失败,当此方法返回时,result 则为 null。If input is null, Empty, or if the conversion fails, result is null when the method returns.
返回
如果 true 参数成功转换,则为 input;否则为 false。true if the input parameter was converted successfully; otherwise, false.
注解
TryParse方法与 Parse 方法类似,不同之处在于,如果转换失败,则它不会引发异常。The TryParse method is similar to the Parse method, except that it doesn't throw an exception if the conversion fails. 相反, false 如果 input 为,它将返回小于 null 两个或四个以上的组件,至少有一个组件不是整数,至少有一个组件小于零,或者至少有一个大于的组件 Int32.MaxValue 。Instead, it returns false if input is null, has fewer than two or more than four components, has at least one component that is not an integer, has at least one component that is less than zero, or has at least one component that is greater than Int32.MaxValue.
若要成功执行分析操作, input 参数必须采用以下格式:For the parse operation to succeed, the input parameter must be in the following format:
major.minor[.build[.revision]]
其中 major ,、、 minor build 和 revision 是版本号的四个组件的字符串表示形式:主要版本号、次版本号、内部版本号和修订号。where major, minor, build, and revision are the string representations of the version number's four components: major version number, minor version number, build number, and revision number, respectively. 可选组件以方括号 ( [和] ) 显示。Optional components are shown in square brackets ([ and ]). 组件必须按顺序显示,并且必须用句点分隔。The components must appear in order and must be separated by periods.
适用于
TryParse(String, Version)
public:
static bool TryParse(System::String ^ input, [Runtime::InteropServices::Out] Version ^ % result);
public static bool TryParse (string input, out Version result);
public static bool TryParse (string? input, out Version? result);
static member TryParse : string * Version -> bool
Public Shared Function TryParse (input As String, ByRef result As Version) As Boolean
参数
- input
- String
包含要转换的版本号的字符串。A string that contains a version number to convert.
- result
- Version
当此方法返回时,如果转换成功,则包含与 input 中所包含的数字等效的 Version。When this method returns, contains the Version equivalent of the number that is contained in input, if the conversion succeeded. 如果 input 为 null、Empty 或者如果转换失败,当此方法返回时,result 则为 null。If input is null, Empty, or if the conversion fails, result is null when the method returns.
返回
如果 true 参数成功转换,则为 input;否则为 false。true if the input parameter was converted successfully; otherwise, false.
示例
下面的示例使用 TryParse 方法分析多个包含版本信息的字符串。The following example uses the TryParse method to parse a number of strings that contain version information.
using System;
public class Example
{
public static void Main()
{
string input = "4.0";
ParseVersion(input);
input = "4.0.";
ParseVersion(input);
input = "1.1.2";
ParseVersion(input);
input = "1.1.2.01702";
ParseVersion(input);
input = "1.1.2.0702.119";
ParseVersion(input);
input = "1.3.5.2150000000";
ParseVersion(input);
}
private static void ParseVersion(string input)
{
Version ver = null;
if (Version.TryParse(input, out ver))
Console.WriteLine("Converted '{0} to {1}.", input, ver);
else
Console.WriteLine("Unable to determine the version from '{0}'.",
input);
}
}
// The example displays the following output:
// Converted '4.0 to 4.0.
// Unable to determine the version from '4.0.'.
// Converted '1.1.2 to 1.1.2.
// Converted '1.1.2.01702 to 1.1.2.1702.
// Unable to determine the version from '1.1.2.0702.119'.
// Unable to determine the version from '1.3.5.2150000000'.
Module Example
Public Sub Main()
Dim input As String = "4.0"
ParseVersion(input)
input = "4.0."
ParseVersion(input)
input = "1.1.2"
ParseVersion(input)
input = "1.1.2.01702"
ParseVersion(input)
input = "1.1.2.0702.119"
ParseVersion(input)
input = "1.3.5.2150000000"
ParseVersion(input)
End Sub
Private Sub ParseVersion(input As String)
Dim ver As Version = Nothing
If Version.TryParse(input, ver) Then
Console.WriteLine("Converted '{0} to {1}.", input, ver)
Else
Console.WriteLine("Unable to determine the version from '{0}'.",
input)
End If
End Sub
End Module
' The example displays the following output:
' Converted '4.0 to 4.0.
' Unable to determine the version from '4.0.'.
' Converted '1.1.2 to 1.1.2.
' Converted '1.1.2.01702 to 1.1.2.1702.
' Unable to determine the version from '1.1.2.0702.119'.
' Unable to determine the version from '1.3.5.2150000000'.
注解
TryParse方法与 Parse 方法类似,不同之处在于,如果转换失败,则它不会引发异常。The TryParse method is similar to the Parse method, except that it doesn't throw an exception if the conversion fails. 相反, false 如果 input 为,它将返回小于 null 两个或四个以上的组件,至少有一个组件不是整数,至少有一个组件小于零,或者至少有一个大于的组件 Int32.MaxValue 。Instead, it returns false if input is null, has fewer than two or more than four components, has at least one component that is not an integer, has at least one component that is less than zero, or has at least one component that is greater than Int32.MaxValue.
若要成功执行分析操作, input 参数必须采用以下格式:For the parse operation to succeed, the input parameter must be in the following format:
major.minor[.build[.revision]]
其中 major ,、、 minor build 和 revision 是版本号的四个组件的字符串表示形式:主要版本号、次版本号、内部版本号和修订号。where major, minor, build, and revision are the string representations of the version number's four components: major version number, minor version number, build number, and revision number, respectively. 可选组件以方括号 ( [和] ) 显示。Optional components are shown in square brackets ([ and ]). 组件必须按顺序显示,并且必须用句点分隔。The components must appear in order and must be separated by periods.