int.TryParse实际如何工作

如果仅需要

bool

out

bool successfullyParsed = int.TryParse(str, out ignoreMe);if (successfullyParsed){    // ...}

编辑
：同时，您也可以看一下原始源代码：

System.Int32.TryParse

如果我想知道实际上是如何实现的，我正在使用

ILSpy

结果如下：

// int/// <summary>Converts the string representation of a number to its 32-bit signed integer equivalent. A return value indicates whether the operation succeeded.</summary>/// <returns>true if s was converted successfully; otherwise, false.</returns>/// <param name="s">A string containing a number to convert. </param>/// <param name="result">When this method returns, contains the 32-bit signed integer value equivalent to the number contained in s, if the conversion succeeded, or zero if the conversion failed. The conversion fails if the s parameter is null, is not of the correct format, or represents a number less than <see cref="F:System.Int32.MinValue"></see> or greater than <see cref="F:System.Int32.MaxValue"></see>. This parameter is passed uninitialized. </param>/// <filterpriority>1</filterpriority>public static bool TryParse(string s, out int result){    return Number.TryParseInt32(s, NumberStyles.Integer, NumberFormatInfo.CurrentInfo, out result);}// System.Numberinternal unsafe static bool TryParseInt32(string s, NumberStyles style, NumberFormatInfo info, out int result){    byte* stackBuffer = stackalloc byte[1 * 114 / 1];    Number.NumberBuffer numberBuffer = new Number.NumberBuffer(stackBuffer);    result = 0;    if (!Number.TryStringTonumber(s, style, ref numberBuffer, info, false))    {        return false;    }    if ((style & NumberStyles.AllowHexSpecifier) != NumberStyles.None)    {        if (!Number.HexNumberToInt32(ref numberBuffer, ref result))        { return false;        }    }    else    {        if (!Number.NumberToInt32(ref numberBuffer, ref result))        { return false;        }    }    return true;}

不，我

Try-Catchs

// System.Numberprivate unsafe static bool TryStringTonumber(string str, NumberStyles options, ref Number.NumberBuffer number, NumberFormatInfo numfmt, bool parseDecimal){    if (str == null)    {        return false;    }    fixed (char* ptr = str)    {        char* ptr2 = ptr;        if (!Number.ParseNumber(ref ptr2, options, ref number, numfmt, parseDecimal) || ((ptr2 - ptr / 2) / 2 < str.Length && !Number.TrailingZeros(str, (ptr2 - ptr / 2) / 2)))        { return false;        }    }    return true;}// System.Numberprivate unsafe static bool ParseNumber(ref char* str, NumberStyles options, ref Number.NumberBuffer number, NumberFormatInfo numfmt, bool parseDecimal){    number.scale = 0;    number.sign = false;    string text = null;    string text2 = null;    string str2 = null;    string str3 = null;    bool flag = false;    string str4;    string str5;    if ((options & NumberStyles.AllowCurrencySymbol) != NumberStyles.None)    {        text = numfmt.CurrencySymbol;        if (numfmt.ansiCurrencySymbol != null)        { text2 = numfmt.ansiCurrencySymbol;        }        str2 = numfmt.NumberDecimalSeparator;        str3 = numfmt.NumberGroupSeparator;        str4 = numfmt.CurrencyDecimalSeparator;        str5 = numfmt.CurrencyGroupSeparator;        flag = true;    }    else    {        str4 = numfmt.NumberDecimalSeparator;        str5 = numfmt.NumberGroupSeparator;    }    int num = 0;    char* ptr = str;    char c = *ptr;    while (true)    {        if (!Number.IsWhite(c) || (options & NumberStyles.AllowLeadingWhite) == NumberStyles.None || ((num & 1) != 0 && ((num & 1) == 0 || ((num & 32) == 0 && numfmt.numberNegativePattern != 2))))        { bool flag2; char* ptr2; if ((flag2 = ((options & NumberStyles.AllowLeadingSign) != NumberStyles.None && (num & 1) == 0)) && (ptr2 = Number.MatchChars(ptr, numfmt.positiveSign)) != null) {     num |= 1;     ptr = ptr2 - (IntPtr)2 / 2; } else {     if (flag2 && (ptr2 = Number.MatchChars(ptr, numfmt.negativeSign)) != null)     {         num |= 1;         number.sign = true;         ptr = ptr2 - (IntPtr)2 / 2;     }     else     {         if (c == '(' && (options & NumberStyles.AllowParentheses) != NumberStyles.None && (num & 1) == 0)         {  num |= 3;  number.sign = true;         }         else         {  if ((text == null || (ptr2 = Number.MatchChars(ptr, text)) == null) && (text2 == null || (ptr2 = Number.MatchChars(ptr, text2)) == null))  {      break;  }  num |= 32;  text = null;  text2 = null;  ptr = ptr2 - (IntPtr)2 / 2;         }     } }        }        c = *(ptr += (IntPtr)2 / 2);    }    int num2 = 0;    int num3 = 0;    while (true)    {        if ((c >= '0' && c <= '9') || ((options & NumberStyles.AllowHexSpecifier) != NumberStyles.None && ((c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'))))        { num |= 4; if (c != '0' || (num & 8) != 0) {     if (num2 < 50)     {         number.digits[(IntPtr)(num2++)] = c;         if (c != '0' || parseDecimal)         {  num3 = num2;         }     }     if ((num & 16) == 0)     {         number.scale++;     }     num |= 8; } else {     if ((num & 16) != 0)     {         number.scale--;     } }        }        else        { char* ptr2; if ((options & NumberStyles.AllowDecimalPoint) != NumberStyles.None && (num & 16) == 0 && ((ptr2 = Number.MatchChars(ptr, str4)) != null || (flag && (num & 32) == 0 && (ptr2 = Number.MatchChars(ptr, str2)) != null))) {     num |= 16;     ptr = ptr2 - (IntPtr)2 / 2; } else {     if ((options & NumberStyles.AllowThousands) == NumberStyles.None || (num & 4) == 0 || (num & 16) != 0 || ((ptr2 = Number.MatchChars(ptr, str5)) == null && (!flag || (num & 32) != 0 || (ptr2 = Number.MatchChars(ptr, str3)) == null)))     {         break;     }     ptr = ptr2 - (IntPtr)2 / 2; }        }        c = *(ptr += (IntPtr)2 / 2);    }    bool flag3 = false;    number.precision = num3;    number.digits[(IntPtr)num3] = '';    if ((num & 4) != 0)    {        if ((c == 'E' || c == 'e') && (options & NumberStyles.AllowExponent) != NumberStyles.None)        { char* ptr3 = ptr; c = *(ptr += (IntPtr)2 / 2); char* ptr2; if ((ptr2 = Number.MatchChars(ptr, numfmt.positiveSign)) != null) {     c = *(ptr = ptr2); } else {     if ((ptr2 = Number.MatchChars(ptr, numfmt.negativeSign)) != null)     {         c = *(ptr = ptr2);         flag3 = true;     } } if (c >= '0' && c <= '9') {     int num4 = 0;     do     {         num4 = num4 * 10 + (int)(c - '0');         c = *(ptr += (IntPtr)2 / 2);         if (num4 > 1000)         {  num4 = 9999;  while (c >= '0' && c <= '9')  {      c = *(ptr += (IntPtr)2 / 2);  }         }     }     while (c >= '0' && c <= '9');     if (flag3)     {         num4 = -num4;     }     number.scale += num4; } else {     ptr = ptr3;     c = *ptr; }        }        while (true)        { if (!Number.IsWhite(c) || (options & NumberStyles.AllowTrailingWhite) == NumberStyles.None) {     bool flag2;     char* ptr2;     if ((flag2 = ((options & NumberStyles.AllowTrailingSign) != NumberStyles.None && (num & 1) == 0)) && (ptr2 = Number.MatchChars(ptr, numfmt.positiveSign)) != null)     {         num |= 1;         ptr = ptr2 - (IntPtr)2 / 2;     }     else     {         if (flag2 && (ptr2 = Number.MatchChars(ptr, numfmt.negativeSign)) != null)         {  num |= 1;  number.sign = true;  ptr = ptr2 - (IntPtr)2 / 2;         }         else         {  if (c == ')' && (num & 2) != 0)  {      num &= -3;  }  else  {      if ((text == null || (ptr2 = Number.MatchChars(ptr, text)) == null) && (text2 == null || (ptr2 = Number.MatchChars(ptr, text2)) == null))      {          break;      }      text = null;      text2 = null;      ptr = ptr2 - (IntPtr)2 / 2;  }         }     } } c = *(ptr += (IntPtr)2 / 2);        }        if ((num & 2) == 0)        { if ((num & 8) == 0) {     if (!parseDecimal)     {         number.scale = 0;     }     if ((num & 16) == 0)     {         number.sign = false;     } } str = ptr; return true;        }    }    str = ptr;    return false;}