1使用unsafe，直接修改字符串

public static class UnsafeString{    public static unsafe void Copy(this string str, LuaString luastr)    {        if (luastr.ptr == IntPtr.Zero)            Clear( str );        fixed (char* pstr = str)        {            var dest = (char*)luastr.ptr.ToPointer();            var len = luastr.len;            for (int i = 0; i < len; i++)                *(pstr + i) = *(dest + i);            *(pstr + len) = '\0';            int* strlen = (int*)pstr - 1;            *strlen = len;        }    }    public static unsafe void Clear(this string str)    {        fixed (char* ptr = str)        {            int* iptr = (int*)ptr - 1;            *iptr = 0;        }    }}

修改text部分

if (txt.text.Length * 2 >= _str.len)//c#是ucs2编码，一个字符是2个字节                {                    txt.text.Copy(_str);                    txt.cachedTextGenerator.Invalidate();                    txt.SetVerticesDirty();                }                else                    txt.text = _str.ToString();

但是有个坑，lua是utf8编码，而c#里是ucs2b编码，所以需要做个转换，明天补上

需要2个方法，一个是获取utf8编码个数

public unsafe int ulen()    {        if (len <= 0) return 0;        if (utf8len > 0) return utf8len;        var str = (byte*)(strdata().ToPointer());        int n = 0;        for (int i = 0; i < len; i++)        {            var c = str[i];            //short c = (short) s;            i += c >= 0xfc ? 5 : (c >= 0xf8 ? 4 : (c >= 0xf0 ? 3 : (c >= 0xe0 ? 2 : (c >= 0xc0 ? 1 : 0))));            n++;        }        utf8len = n;        return utf8len;    }

一个是从utf8转到unicode(utf16)

public static unsafe void CopyAnsi(this string str, LuaString luastr)    {        if (luastr.ptr == IntPtr.Zero)            Clear(str);        fixed (char* pstr = str)        {            var dest = (byte*)luastr.strdata().ToPointer();            var len = luastr.len;            var pstrn = 0;            int oldlen = *((int*)pstr - 1);            for (int i = 0; i < len; i++)            {                var c = *(dest + i);                if (c >= 0xfc)                {                }                else if (c >= 0xf8)                {                }                else if (c >= 0xf0)                {                }                else if (c >= 0xe0)                {                    var c1 = * (dest + i + 1);                    var c2 = * (dest + i + 2);                    *(pstr + pstrn) = (char)(((c & 0x1f) << 12) + ((c1 & 0x3f) << 6)+ (c2 & 0x3f));                    i += 2;                }                else if (c >= 0xc0)                {                    var c1 = *(dest + i + 1);                    *(pstr + pstrn) = (char)(((c & 0x3c) << 6) + (c1 & 0x3f));                    i++;                }                else                {                   * (pstr + pstrn) = (char)c;                }                pstrn++;            }            //*(pstr + pstrn) = (byte)0;            int* strlen = (int*)pstr - 1;            *strlen = pstrn;        }    }

修改text部分

set {            if(!(c is Text) && !(c is InputField)) Log.Assert((c is Text), "the component name {0} is not a Text or InputField", c.name);            if (c is Text)            {                if (_str.ptr == value.str.ptr) return;                unrefString(_str);                _str = value.str;                var txt = (c as Text);                if (txt.text.Length >= _str.ulen())                {                    //txt.text.Copy(_str);                    txt.text.CopyAnsi(_str);                    txt.cachedTextGenerator.Invalidate();                    txt.SetVerticesDirty();                }                else                    txt.text = _str.ToString();                refString(_str);                            }            if (c is InputField) (c as InputField).text = (string)value;        }