blocks|key|1035633|text|Convert.ToString()处理null，而ToString()不处理。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1035634|entityMap^0|0|I|K|4|Q|A|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|O|8|@]|D|@]|E|$]]]|G|$]]

<code>Convert.ToString()</code> handles <code>null</code>, while <code>ToString()</code> doesn't.

blocks|key|1250951|text|除了有关处理null值的其他答案之外，Convert.ToString还会在调用基本Object.ToString之前尝试使用IFormattable和IConvertible接口。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1250952|示例：|1250953|class+FormattableType+:+IFormattable
{
++++private+double+value+=+0.42;

++++public+string+ToString(string+format,+IFormatProvider+formatProvider)
++++{
++++++++if+(formatProvider+==+null)
++++++++{
++++++++++++//+...+using+some+IOC-containers
++++++++++++//+...+or+using+CultureInfo.CurrentCulture+/+Thread.CurrentThread.CurrentCulture
++++++++++++formatProvider+=+CultureInfo.InvariantCulture;
++++++++}

++++++++//+...+doing+things+with+format
++++++++return+value.ToString(formatProvider);
++++}

++++public+override+string+ToString()
++++{
++++++++return+value.ToString();
++++}
}|code-block|syntax|javascript|1250954|结果：|1250955|Convert.ToString(new+FormattableType());+//+0.42
new+FormattableType().ToString();++++++++//+0,42|1250956|entityMap^0|6|4|J|G|16|F|1R|C|24|C|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]|$9|Z|A|10|B|C]|$9|11|A|12|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|13|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|14|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|15|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|16|8|@]|D|@]|E|$K|L]]|$1|Q|3|-4|5|6|7|17|8|@]|D|@]|E|$]]]|R|$]]

In addition to other answers about handling <code>null</code> values, <code>Convert.ToString</code> tries to use <code>IFormattable</code> and <code>IConvertible</code> interfaces before calling base <code>Object.ToString</code>.

Example:

<pre><code>class FormattableType : IFormattable
{
 private double value = 0.42;

 public string ToString(string format, IFormatProvider formatProvider)
 {
 if (formatProvider == null)
 {
 // ... using some IOC-containers
 // ... or using CultureInfo.CurrentCulture / Thread.CurrentThread.CurrentCulture
 formatProvider = CultureInfo.InvariantCulture;
 }

 // ... doing things with format
 return value.ToString(formatProvider);
 }

 public override string ToString()
 {
 return value.ToString();
 }
}
</code></pre>

Result:

<pre><code>Convert.ToString(new FormattableType()); // 0.42
new FormattableType().ToString(); // 0,42
</code></pre>

blocks|key|1250850|text|让我们通过这个例子来理解其中的区别：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1250851|int+i=+0;
MessageBox.Show(i.ToString());
MessageBox.Show(Convert.ToString(i));|code-block|syntax|javascript|1250852|我们可以使用i.ToString+()或Convert.ToString转换整数i。那么有什么不同呢？|offset|length|style|CODE|1250853|它们之间的基本区别是Convert函数处理NULL，而i.ToString+()不处理；它将抛出NULL引用异常错误。因此，使用convert进行良好的编码实践总是安全的。|1250854|entityMap^0|0|0|6|D|K|G|14|1|0|A|7|R|D|1S|7|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]|$I|V|J|W|K|L]|$I|X|J|Y|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|Z|8|@$I|10|J|11|K|L]|$I|12|J|13|K|L]|$I|14|J|15|K|L]]|9|@]|A|$]]|$1|O|3|-4|5|6|7|16|8|@]|9|@]|A|$]]]|P|$]]

Lets understand the difference via this example:

<pre><code>int i= 0;
MessageBox.Show(i.ToString());
MessageBox.Show(Convert.ToString(i));
</code></pre>

We can convert the integer <code>i</code> using <code>i.ToString ()</code> or <code>Convert.ToString</code>. So what’s the difference? 

The basic difference between them is the <code>Convert</code> function handles NULLS while <code>i.ToString ()</code> does not; it will throw a NULL reference exception error. So as good coding practice using <code>convert</code> is always safe.

blocks|key|1250879|text|object+o=null;
string+s;
s=o.toString();
//returns+a+null+reference+exception+for+string++s.

string+str=convert.tostring(o);
//returns+an+empty+string+for+string+str+and+does+not+throw+an+exception.,it's+
//better+to+use+convert.tostring()+for+good+coding|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1250880|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>object o=null;
string s;
s=o.toString();
//returns a null reference exception for string s.

string str=convert.tostring(o);
//returns an empty string for string str and does not throw an exception.,it's 
//better to use convert.tostring() for good coding
</code></pre>

blocks|key|1250765|text|在Convert.ToString()中，转换可以处理NULL值，也可以不处理，但在.ToString()中，它不处理NULL值和NULL引用异常错误。因此，使用Convert.ToString()是一个很好的实践。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1250766|entityMap^0|1|I|R|4|16|B|1N|4|1T|4|29|I|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]|$9|O|A|P|B|C]|$9|Q|A|R|B|C]|$9|S|A|T|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|U|8|@]|D|@]|E|$]]]|G|$]]

In <code>Convert.ToString()</code>, the Convert handles either a <code>NULL</code> value or not but in <code>.ToString()</code> it does not handles a <code>NULL</code> value and a <code>NULL</code> reference exception error. So it is in good practice to use <code>Convert.ToString()</code>.

blocks|key|1036001|text|Convert.ToString(strName)将处理支持空值的值，而strName.Tostring()将不会处理空值并抛出异常。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1036002|因此，使用Convert.ToString()比使用.ToString();更好|1036003|entityMap^0|0|P|10|I|0|5|I|Q|C|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|I|$]]

<code>Convert.ToString(strName)</code> will handle null-able values and <code>strName.Tostring()</code> will not handle null value and throw an exception.

So It is better to use <code>Convert.ToString()</code> then <code>.ToString();</code>

blocks|key|1250997|text|ToString()不能处理空值，而convert.ToString()可以处理空值，所以当您希望系统处理空值时，请使用convert.ToString()。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1250998|entityMap^0|0|A|I|I|1O|I|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|O|8|@]|D|@]|E|$]]]|G|$]]

<code>ToString()</code> can not handle null values and <code>convert.ToString()</code> can handle values which are null, so when you want your system to handle null value use <code>convert.ToString()</code>.

blocks|key|1036071|text|为了理解这两种方法，让我们举个例子：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1036072|int+i+=0;
MessageBox.Show(i.ToString());
MessageBox.Show(Convert.ToString(i));+|code-block|syntax|javascript|1036073|这里这两种方法都用来转换字符串，但它们之间的基本区别是：Convert函数处理NULL，而i.ToString()不处理，它将抛出NULL+reference+exception+error.，因此使用convert进行良好的编码实践总是安全的。|offset|length|style|CODE|1036074|让我们看另一个例子：|1036075|string+s;
object+o+=+null;
s+=+o.ToString();+
//returns+a+null+reference+exception+for+s.+

string+s;
object+o+=+null;
s+=+Convert.ToString(o);+
//returns+an+empty+string+for+s+and+does+not+throw+an+exception.|1036076|entityMap^0|0|0|S|7|13|4|19|C|1T|V|2T|7|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@$I|V|J|W|K|L]|$I|X|J|Y|K|L]|$I|Z|J|10|K|L]|$I|11|J|12|K|L]|$I|13|J|14|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|15|8|@]|9|@]|A|$]]|$1|O|3|P|5|D|7|16|8|@]|9|@]|A|$E|F]]|$1|Q|3|-4|5|6|7|17|8|@]|9|@]|A|$]]]|R|$]]

To understand both the methods let's take an example: 

<pre><code>int i =0;
MessageBox.Show(i.ToString());
MessageBox.Show(Convert.ToString(i)); 
</code></pre>

Here both the methods are used to convert the string but the basic difference between them is: <code>Convert</code> function handles <code>NULL</code>, while <code>i.ToString()</code> does not it will throw a <code>NULL reference exception error.</code> So as good coding practice using <code>convert</code> is always safe.

Let's see another example: 

<pre><code>string s;
object o = null;
s = o.ToString(); 
//returns a null reference exception for s. 

string s;
object o = null;
s = Convert.ToString(o); 
//returns an empty string for s and does not throw an exception.
</code></pre>

blocks|key|1036118|text|Convert.Tostring()函数处理NULL，而.ToString()方法不处理。请访问here。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1036119|entityMap|0|LINK|mutability|MUTABLE|url|https://devbloggies.blogspot.com/2019/07/difference-between-convert.tostring-and-.tostring-method-in-c-sharp.html^0|1C|4|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

Convert.Tostring() function handles the NULL whereas the .ToString() method does not. visit <a href="https://devbloggies.blogspot.com/2019/07/difference-between-convert.tostring-and-.tostring-method-in-c-sharp.html" rel="nofollow noreferrer">here</a>.

blocks|key|1036185|text|在C#中，如果您声明了一个字符串变量，并且没有为该变量赋值，那么在缺省情况下，该变量将采用空值。在这种情况下，如果您使用ToString()方法，那么您的程序将抛出空引用异常。另一方面，如果您使用Convert.ToString()方法，那么您的程序不会抛出异常。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1036186|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

In C# if you declare a string variable and if you don’t assign any value to that variable, then by default that variable takes a null value. In such a case, if you use the ToString() method then your program will throw the null reference exception. On the other hand, if you use the Convert.ToString() method then your program will not throw an exception.

What is the difference between <code>Convert.ToString()</code> and <code>.ToString()</code>?

I found many differences online, but what's the major difference?

Difference between Convert.ToString() and .ToString()

Convert.ToString()和.ToString()之间的区别是什么我在网上发现了很多不同之处，但最主要的区别是什么呢？

问Convert.ToString()和.ToString()之间的区别
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