Question

使用此代码......

Imports System.CodeDom.Compiler

Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim sb As New System.Text.StringBuilder
        sb.AppendLine("Imports System")
        sb.AppendLine("Imports System.Xml")
        sb.AppendLine("Imports System.Data")
        sb.AppendLine("Imports System.Collections.Generic")
        sb.AppendLine("Namespace dValuate")
        sb.AppendLine("Class EvalRunTime")
        sb.AppendLine("Public Function EvaluateIt() As Object")
        sb.AppendLine("{0}")
        sb.AppendLine("End Function")
        sb.AppendLine("End Class")
        sb.AppendLine("End Namespace")

        Dim testCode As String = "Dim d As Decimal = ""a"""

        Dim provider As VBCodeProvider = New VBCodeProvider
        Dim params As CompilerParameters = New CompilerParameters
        Dim results As CompilerResults
        params.ReferencedAssemblies.Add("system.dll")
        params.ReferencedAssemblies.Add("system.xml.dll")
        params.ReferencedAssemblies.Add("system.data.dll")
        params.ReferencedAssemblies.Add("System.Windows.Forms.dll")
        params.CompilerOptions = "/t:library"
        params.GenerateInMemory = True
        results = provider.CompileAssemblyFromSource(params, String.Format(sb.ToString, testCode))

        sb.Length = 0
        If results.Errors.Count > 0 Then
            For Each err As CompilerError In results.Errors
                sb.AppendLine("Line: " + err.Line.ToString + ", Error: " + err.ErrorText)
            Next
            MsgBox(sb.ToString)
        End If
    End Sub
End Class

当我尝试将小数设置为字符串时，为什么results.Errors.Count = 0？

有没有办法捕捉到这个错误？

Answer 1

您需要Option Strict On告诉VB编译器在编译时实际检查类型兼容性。

PS：考虑使用Roslyn而不是CodeDom。

Answer 2

如果没有在严格模式下编译，则将字符串隐式转换为数字不是编译器错误。

将选项strict的开关添加到编译器选项：

params.CompilerOptions = "/t:library /optionstrict"

即时编译不会发现错误 - 为什么？

2 个答案: