resolved #197

Author: ymh199478

src/CatLib.Core.Tests/Support/Util/StrTests.cs

@@ -264,19 +264,25 @@ public void TestRandom()
             Assert.AreEqual(16, str.Length);
         }
 
+        [TestMethod]
+        public void TestStrSpace()
+        {
+            Assert.AreEqual(" ", Str.Space);
+        }
+
         [TestMethod]
         public void TestTruncate()
         {
             var str = Str.Truncate("hello world , the sun is shine", 11);
             Assert.AreEqual("hello wo...", str);
 
-            str = Str.Truncate("hello world , the sun is shine", 11, " ");
+            str = Str.Truncate("hello world , the sun is shine", 11, Str.Space);
             Assert.AreEqual("hello...", str);
 
-            str = Str.Truncate("hello world , the sun is shine", 15, " ");
+            str = Str.Truncate("hello world , the sun is shine", 15, Str.Space);
             Assert.AreEqual("hello world...", str);
 
-            str = Str.Truncate("hello world sun sname", 15, " ");
+            str = Str.Truncate("hello world sun sname", 15, Str.Space);
             Assert.AreEqual("hello world..." , str);
 
             var regex = new Regex("orl");

src/CatLib.Core/Support/Util/Str.cs

@@ -41,6 +41,11 @@ public enum PadTypes
             Right
         }
 
+        /// <summary>
+        /// 空格字符串
+        /// </summary>
+        public const string Space = " ";
+
         /// <summary>
         /// 获取字符串所表达的函数名
         /// </summary>
@@ -305,8 +310,8 @@ public static string Pad(string str, int length, string padStr = null, PadTypes
                 leftPadding = needPadding;
             }
 
-            padStr = padStr ?? " ";
-            padStr = padStr.Length <= 0 ? " " : padStr;
+            padStr = padStr ?? Space;
+            padStr = padStr.Length <= 0 ? Space : padStr;
 
             var leftPadCount = leftPadding / padStr.Length + (leftPadding % padStr.Length == 0 ? 0 : 1);
             var rightPadCount = rightPadding / padStr.Length + (rightPadding % padStr.Length == 0 ? 0 : 1);
@@ -438,7 +443,7 @@ public static string Random(int length = 16, int? seed = null)
 
         /// <summary>
         /// 如果长度超过给定的最大字符串长度，则截断字符串。 截断的字符串的最后一个字符将替换为缺省字符串
-        /// <para>eg: Str.Truncate("hello world , the sun is shine",15," ") => hello world...</para>
+        /// <para>eg: Str.Truncate("hello world , the sun is shine", 15, Str.Space) => hello world...</para>
         /// </summary>
         /// <param name="str">要截断的字符串</param>
         /// <param name="length">截断长度(含缺省字符长度)</param>