另一种方法是使用StringComparison选项忽略String.Replace()中的大小写敏感性。CurrentCultureIgnoreCase

string.Replace("World", "csharp", StringComparison.CurrentCultureIgnoreCase)

使用这个，测试和100%工作!

VB。网

Dim myString As String
Dim oldValue As String
Dim newValue As String

myString = Form1.TextBox1.Text
oldValue = TextBox1.Text
newValue = TextBox2.Text

Dim working As String = myString
Dim index As Integer = working.IndexOf(oldValue, StringComparison.CurrentCultureIgnoreCase)

While index <> -1
    working = working.Remove(index, oldValue.Length)
    working = working.Insert(index, newValue)
    index = index + newValue.Length
    index = working.IndexOf(oldValue, index, StringComparison.CurrentCultureIgnoreCase)
    Form1.TextBox1.Text = working
End While

为c#

private void Button2_Click(System.Object sender, System.EventArgs e)
{
    string myString;
    string oldValue;
    string newValue;

    myString = Form1.TextBox1.Text;
    oldValue = TextBox1.Text;
    newValue = TextBox2.Text;

    string working = myString;
    int index = working.IndexOf(oldValue, StringComparison.CurrentCultureIgnoreCase);

    while (index != -1)
    {
        working = working.Remove(index, oldValue.Length);
        working = working.Insert(index, newValue);
        index = index + newValue.Length;
        index = working.IndexOf(oldValue, index, StringComparison.CurrentCultureIgnoreCase);
        Form1.TextBox1.Text = working;
    }
}

我更喜欢这个- "Hello World". tolower()。Replace("world"， " chsharp ");

另一种方法是使用StringComparison选项忽略String.Replace()中的大小写敏感性。CurrentCultureIgnoreCase

string.Replace("World", "csharp", StringComparison.CurrentCultureIgnoreCase)

这样不行吗?我想象不出还有什么比这更快更简单的方法了。

public static class ExtensionMethodsString
{
    public static string Replace(this String thisString, string oldValue, string newValue, StringComparison stringComparison)
    {
        string working = thisString;
        int index = working.IndexOf(oldValue, stringComparison);
        while (index != -1)
        {
            working = working.Remove(index, oldValue.Length);
            working = working.Insert(index, newValue);
            index = index + newValue.Length;
            index = working.IndexOf(oldValue, index, stringComparison);
        }
        return working;
    }
}

你可以用微软。VisualBasic命名空间来查找这个帮助函数:

Replace(sourceString, "replacethis", "withthis", , , CompareMethod.Text)